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Background Despite extensive research on microbiome alterations in ulcerative colitis (UC), the role of the constituent stable microbiota remains unclear. Results This study, employing 16S rRNA-gene sequencing, uncovers a persistent microbial imbalance in both active and quiescent UC patients compared to healthy controls. Using co-occurrence and differential abundance analysis, the study highlights microbial constituents, featuring Phocaeicola, Collinsella, Roseburia, Holdemanella, and Bacteroides, that are not affected during the course of UC. Co-cultivation experiments, utilizing commensal Escherichia coli and Phocaeicola vulgatus, were conducted with intestinal epithelial organoids derived from active UC patients and controls. These experiments reveal a tendency for a differential response in tight junction formation and maintenance in colonic epithelial cells, without inducing pathogen recognition and stress responses, offering further insights into the roles of these microorganisms in UC pathogenesis. These experiments also uncover high variation in patients' response to the same bacteria, which indicate the need for more comprehensive, stratified analyses with an expanded sample size. Conclusion This study reveals that a substantial part of the gut microbiota remains stable throughout progression of UC. Functional experiments suggest that members of core microbiota - Escherichia coli and Phocaeicola vulgatus - potentially differentially regulate the expression of tight junction gene in the colonic epithelium of UC patients and healthy individuals. Keywords: Ulcerative colitis, Gut microbiota, Escherichia coli, Phocaeicola vulgatus, Colonic epithelial organoids, Colonic epithelial barrier, Crosstalk, Author(s): Ruta Inciuraite[sup.1], Rolandas Gedgaudas[sup.1,2], Rokas Lukosevicius[sup.1], Deimante Tilinde[sup.1], Rima Ramonaite[sup.1], Alexander Link[sup.3], Neringa Kasetiene[sup.4], Mindaugas Malakauskas[sup.4], Gediminas Kiudelis[sup.1,2], Laimas Virginijus Jonaitis[sup.1,2], Juozas Kupcinskas[sup.1,2], Simonas Juzenas[sup.1,5] and Jurgita Skieceviciene[sup.1] Background [...]

Biodegradable packaging, both alone and in combination with acid whey protein coatings, has been used to pack fresh Gouda cheese to improve preservation prior ripening or storage. This study involved three key components: (i) the selection of biodegradable packaging (BP), (ii) the development of a plain liquid acid whey protein concentrate, pectin-based edible coating (BP + Ch + Coating), and (iii) the incorporation of at least 6 log10 CFU (colony forming units) mL−1 Lacticaseibacillus paracasei (BP + Ch + Coating + Lp) and Lactobacillus helveticus (BP + Ch + Coating + Lh) strains. The created compositions were compared with cheese packed in conventional polyethylene (PE) packaging to evaluate their overall synergy effect in reducing microbiological spoilage and influencing chemical parameters in Gouda cheese during 45 days of ripening and cold storage. The evaluation included microbiological analysis (total LAB, Enterobacteriaceae spp., and fungi CFU) and quality assessment of pH, moisture content, water activity, texture, and colour (CEI system) during ripening and shelf life. Although biodegradable packaging (BP) alone did not protect the cheese effectively compared to conventional packaging (EVA/PE/EPC/PVDC), the combination of biodegradable packaging with a coating (BP + Ch + Coating) showed protective properties against Enterobacteriaceae spp. and mould, maintaining moisture, pH, and colour during ripening and storage. Incorporation of L. helveticus (BP + Ch + Coating + Lh) into the coating efficiently decreased the growth of fungi. [ABSTRACT FROM AUTHOR]

The use of lactic acid bacteria (LAB) in the fermentation process to produce fermented foods has a long history. Furthermore, LAB are beneficial microorganisms known for their health-promoting characteristics. During fermentation, LAB have the capacity to produce significant amounts of bioactive substances, such as peptides, bacteriocins, lactic acid, exopolysaccharides (EPSs), enzymes, and others. Lactococcus lactis as one of the best-known and well-characterized species of LAB serves as a model organism for studying LAB. For a very long time, L. lactis has been used in milk fermentation, both in well-monitored industrial settings and on a small scale in traditional operations. Furthermore, L. lactis is a vital microorganism in the dairy food fermentation industry due to its role in acidification, flavor development, and the creation of various dairy products, including cheese, fermented butter, and others. The novelty of this review is the comprehensive and organized presentation of the main benefits of the use of L. lactis in milk fermentation processes including technological and safety features relevant for the dairy industry, probiotic potential, the ability to produce bioactive compounds (e.g., bacteriocins, GABA), and the recent development of such bacteria research methods like whole genome sequencing (WGS). [ABSTRACT FROM AUTHOR]

Summary: Consumer interest in a healthy lifestyle and health‐promoting natural products is a major driving force for the increasing global demand for bio‐functional and sustainable dairy foods. Supplementation of curd cheese with thermo‐coagulated acid whey protein (TAWP) led to 8–10% higher contents of moisture, 23–31% of lactose, 12–13% of unsaturated, 5–6% of monounsaturated, 63% of polyunsaturated, and 3–4% of long‐chain fatty acids. Lipid quality indices – TI, AI, h/H, and Omega 6/3 among others, were also significantly better than those of control cheese. The addition of indigenous Lactococcus lactis strain enhanced the flavour of cheese samples, decreased the counts of yeast and mould up to 1 log cfu g−1 after 10 days of storage. The replacement of curd with TAWP resulted in novel cheese with overall sensory perception above 77 points and added nutritional and functional value, however, body and texture parameters of modified cheese samples require an improvement. [ABSTRACT FROM AUTHOR]

The aim of our studies was to evaluate rep-PCR typing using different primers as a fast genotyping method for discrimination of C. jejuni. Also a microfluidic electrophoretic DNA separation method for rapid DNA fingerprinting based on Lab-on-a-Chip technology was tested. Based on the test results, the single polytrinucleotide (GTG)5 was chosen as primer. Nine strains representing three epidemiological groups from the CAMPYNET network strains were assigned to three different groups by both (GTG)5- PCR and PFGE. Typing of 72 epidemiologically independent strains using (GTG)5-PCR and PFGE clustered the strains in 60 and 53 clusters, respectively, with an identical discriminatory power (D=0,99). When PCR-products were separated on the Agilent 2100 Bioanalyzer Lab-on-a-Chip device the strains were grouped with the same discriminatory power, though some strains were clustered differently compare to gel-based DNA amplicon separation. The main disadvantage of (GTG)5-PCR typing was differences in band intensity that complicates comparison of (GTG)5-PCR fingerprints when numerous strains are evaluated. The advantages of rep-PCR based subtyping were rapidity, simplicity, similar discriminatory power to PFGE and possible rapid DNA amplicon separation based on Lab-on-a-Chip technology with Agilent 2100 Bioanalyzer. [ABSTRACT FROM AUTHOR]

Various animal species, wild birds, rodents and pets are the main source of Campylobacter contamination in broiler farms. However, little is known about the ability of these bacteria to survive outside the host and their role in the colonisation of broilers. Therefore, in this study we aimed to identify the sources of Campylobacter in poultry farm environment and their significance for broiler colonisation. For this purpose, Campylobacter spp. were isolated from broilers and their environment (litter, water of puddle, concentric zones, tap water) by both direct inoculation on mCCDA selective medium and selective enrichment into Exeter broth. Campylobacter isolates were identified to the species level by multiplex polymerase chain reaction. The genetic diversity of Campylobacter jejuni strains isolated from broilers and the environment was examined by PCR-based restriction fragment length polymorphism analysis of PCR amplified portion of the flagellin-A (flaA) gene. The results revealed that 28.5% out of 752 samples were contaminated with Campylobacter spp. The flaA-RFLP analysis of 263 C. jejuni isolates revealed 21 different flaA genotypes. Each broiler flock had specific Campylobacter genotypes, which had not been transmitted to other broiler flocks reared in the same building. Studies have shown that Campylobacter can survive in poultry environment. They can be transferred from the environment into broiler houses by shoes, cloths and wildlife. Therefore, strict bio-security and hygiene rules must be implemented at the farm level to prevent spread of this pathogen. Additionally, hostile environment for pathogenic bacteria must be established in the areas around a broiler house. [ABSTRACT FROM AUTHOR]