Fresh samples of intestinal contents of three wild pigs originating from the Central Bohemia region were examined for the presence of bifidobacterial strains. During the study, we isolated many fructose-6-phosphate phosphoketolase-positive, strictly anaerobic, irregular rod-shaped bacterial isolates. Three of them were preliminarily identified as representing a novel species of the genus Bifidobacterium because their 16S rRNA gene sequence similarity with the closest relatives of thermophilic bifidobacteria ( Bifidobacterium boum DSM 20432T, Bifidobacterium thermophilum DSM 20210T, Bifidobacterium thermacidophilum subsp. porcinum LMG 21689T, Bifidobacterium thermacidophilum subsp. thermacidophilum DSM 15837T) was in the range of 97.9 – 98.4 %. All three bacterial isolates had identical 16S rRNA, dnaJ1, fusA, gyrB and rplB gene sequences. Isolate RP115T was chosen as a representative of the bacterial group and DNA G+C content (mol%) determination, biochemical tests and analyses of physiological and morphological characteristics, habitat and chemotaxonomic traits (peptidoglycan structure, cellular fatty acids and polar lipids profile) were performed. The DNA–DNA hybridization analyses of RP115T and species representing the group of thermophilic bifidobacteria revealed values in the range from 33 to 53 %. This fact, together with relatively low sequence similarities of particular phylogenetic markers among examined bacterial strains and the phenotyping and chemotaxonomy results obtained, indicated that the evaluated bacterial isolate should be classified as representing a separate taxon within the specific group of thermophilic bifidobacteria. The name Bifidobacterium apri (of boar) sp. nov. has been proposed for the representative strain RP115T (=CCM 8605T=DSM 100238T=LMG 28779T).

Non-typhoid Salmonellae are worldwide spread food-borne pathogens that cause diarrhea in humans and animals. Their multi-drug resistances require alternative ways to combat this enteric pathogen. Mono-colonization of a gnotobiotic piglet gastrointestinal tract with commensal lactobacilli Lactobacillus amylovorus and Lactobacillus mucosae and with probiotic E. coli Nissle 1917 and their interference with S. Typhimurium infection was compared. The impact of bacteria and possible protection against infection with Salmonella were evaluated by clinical signs, bacterial translocation, intestinal histology, mRNA expression of villin, claudin-1, claudin-2, and occludin in the ileum and colon, and local intestinal and systemic levels of inflammatory cytokines IL-8, TNF-α, and IL-10. Both lactobacilli colonized the gastrointestinal tract in approximately 100× lower density compare to E. coli Nissle and S. Typhimurium. Neither L. amylovorus nor L. mucosae suppressed the inflammatory reaction caused by the 24 h infection with S. Typhimurium. In contrast, probiotic E. coli Nissle 1917 was able to suppress clinical signs, histopathological changes, the transcriptions of the proteins, and the inductions of the inflammatory cytokines. Future studies are needed to determine whether prebiotic support of the growth of lactobacilli and multistrain lactobacilli inoculum could show higher protective effects.

The mode of delivery plays a crucial role in infant gastrointestinal tract colonisation, which in the case of caesarean section is characterised by the presence of clostridia and low bifidobacterial counts. Gut colonisation can be modified by probiotics, prebiotics or synbiotics. Human milk oligosaccharides (HMOs) are infant prebiotics that show a bifidogenic effect. Moreover, genome sequencing ofBifidobacterium longumsubsp.infantiswithin the infant microbiome revealed adaptations for milk utilisation. This study aimed to evaluate the synbiotic effect ofB. longumsubsp.infantis, HMOs and human milk (HM) bothin vitroandin vivo(in a humanised mouse model) in the presence of faecal microbiota from infants born by caesarean section. The combination ofB. longumand HMOs or HM reduced the clostridia and G-bacteria counts bothin vitroandin vivo. The bifidobacterial populationin vitrosignificantly increased and produce high concentrations of acetate and lactate.In vitrocompetition assays confirmed that the tested bifidobacterial strain is a potential probiotic for infants and, together with HMOs or HM, acts as a synbiotic. It is also able to inhibit potentially pathogenic bacteria. The synbiotic effects identifiedin vitrowere not observedin vivo. However, there was a significant reduction in clostridia counts in both experimental animal groups (HMOs +B. longumand HM +B. longum), and a specific immune response via increased interleukin (IL)-10 and IL-6 production. Animal models do not perfectly mimic human conditions; however, they are essential for testing the safety of functional foods.

Bacteria with potential probiotic applications are not yet sufficiently explored, even for animals with economic importance. Therefore, we decided to isolate and identify representatives of the family Bifidobacteriaceae , which inhabit the crop of laying hens. During the study, a fructose-6-phosphate phosphoketolase-positive strain, RP51T, with a regular/slightly irregular and sometimes an S-shaped slightly curved rod-like shape, was isolated from the crop of a 13 -month-old Hisex Brown hybrid laying hen. The best growth of the Gram-stain-positive bacterium, which was isolated using Bifidobacterium -selective mTPY agar, was found out to be under strictly anaerobic conditions, however an ability to grow under microaerophilic and aerobic conditions was also observed. Sequencing of the almost complete 16S rRNA gene (1444 bp) showed Alloscardovia omnicolens CCUG 31649T and Bombiscardovia coagulans BLAPIII/AGVT to be the most closely related species with similarities of 93.4 and 93.1 %, respectively. Lower sequence similarities were determined with other scardovial genera and other representatives of the genus Bifidobacterium . Taxonomic relationships with A. omnicolens and other members of the family Bifidobacteriaceae were also demonstrated, based on the sequences of dnaK, fusA, hsp60 and rplB gene fragments. Low sequence similarities of phylogenetic markers to related scardovial genera and bifidobacteria along with unique features of the bacterial strain investigated within the family Bifidobacteriaceae ( including the lowest DNA G+C value (44.3 mol%), a unique spectrum of cellular fatty acids and polar lipids, cellular morphology, the wide temperature range for growth (15–49 °C) and habitat) clearly indicate that strain RP51T is a representative of a novel genus within the family Bifidobacteriaceae for which the name Galliscardovia ingluviei gen. nov., sp. nov. (RP51T=DSM 100235T=LMG 28778T=CCM 8606T) is proposed.

The ability of bacteria to adhere to the intestinal mucosa is a critical property necessary for the long-term colonization of the intestinal tract. This ability can be highly sensitive to the presence of prebiotics. However, limited data are available in this respect for beneficial bacteria such as probiotics or resident gut microbiota. We previously demonstrated that the presence of prebiotics may decrease adherence in several pre- and probiotic combinations. Thus, characterizing the interactions between numerous combinations involving different classes of pre- and probiotics can be crucial in identifying new synbiotics. Accordingly, here, we extend our prior analyses to evaluate the adhesion of five lactobacilli, six bifidobacteria, and one probiotic Escherichia coli strains, as commercial probiotics or promising probiotic candidates, together with the cariogenic Bifidobacterium dentium strain. As an in vitro intestinal mucosa model, Caco-2 and mucin-secreting HT29-MTX cells were co-cultured at 9:1 in the presence or absence of prebiotics. Commercial inulin-type fructooligosaccharide prebiotics Orafti^® GR, Orafti^® P95, and galactooligosaccharide-based prebiotic formula Vivinal^®, including purified human milk oligosaccharides (HMOs) were added into the cultivation media as the sole sugar source (2.5% each). Adherence was tested using microtiter plates and was evaluated as the percentage of fluorescently labeled bacteria present in the wells after three washes. Consistent prebiotics-mediated enhanced adherence was observed only for the commercial probiotic strain E. coli O83. For the remaining strains, the presence of HMO or prebiotics Orafti^® P95 or Orafti^® GR decreased adherence, reaching statistical significance (p < 0.05) for three of out of eight (HMO) or five of out of 11 strains tested, respectively. Conversely, Vivinal^® enhanced adhesion in six out of the 12 strains tested, and notably, it significantly attenuated the adherence of the cariogenic Bifidobacterium dentium Culture Collection of Dairy Microorganisms (CCDM) 318. To our knowledge, this represents the first report on the influence of commercial prebiotics and HMOs on the adhesion of the cariogenic Bifidobacterium sp. Vivinal^® seems to be a promising prebiotic to be used in the formulation of synbiotics, supporting the adhesion of a wide range of probiotics, especially the strains B. bifidum BBV and BBM and the probiotic Escherichia coli O83.