Promising Probiotic Strain Research Articles

In Vitro Selection of Lactobacillus and Bifidobacterium Probiotic Strains for the Management of Oral Pathobiont Infections Associated to Systemic Diseases

The human oral pathobionts Aggregatibacter actinomycetemcomitans, Streptococcus mitis and Streptococcus mutans, in dysbiosis-promoting conditions, lead to oral infections, which also represent a threat to human systemic health. This scenario may be worsened by antibiotic misuse, which favours multi-drug resistance, making the research on pathogen containment strategies more than crucial. Therefore, we aimed to in vitro select the most promising probiotic strains against oral pathogen growth, viability, biofilm formation, and co-aggregation capacity, employing both the viable probiotics and their cell-free supernatants (CFSs). Interestingly, we also assessed probiotic efficacy against the three-pathogen co-culture, mimicking an environment similar to that in vivo. Overall, the results showed that Lactobacillus CFSs performed better than the Bifidobacterium, highlighting Limosilactobacillus reuteri LRE11, Lacticaseibacillus rhamnosus LR04, Lacticaseibacillus casei LC04, and Limosilactobacillus fermentum LF26 as the most effective strains, opening the chance to deeper investigation of their action and CFS composition. Altogether, the methodologies presented in this study can be used for probiotic efficacy screenings, in order to better focus the research on a viable probiotic, or on its postbiotics, suitable in case of infections.

Lactobacillus helveticus HY7801 ameliorates bacterial vaginosis by inhibiting biofilm formation and epithelial cell adhesion of Gardnerella vaginalis

Bacterial vaginosis (BV) is caused by a microbial imbalance in the vaginal ecosystem, which causes genital discomfort and a variety of potential complications in women. This study validated the potential of Lactobacillus helveticus HY7801 as a probiotic to benefit vaginal health. In vivo, HY7801 reduced the number of Gardnerella vaginalis (GV) and pro-inflammatory cytokines in the vagina of GV-induced BV mice and ameliorated vaginal histological changes. In vitro, HY7801 exhibited positive resistance to simulated gastrointestinal conditions, showed excellent adherence ability to the female genital epithelium, and had high lactic acid and H2O2 production capacity. Furthermore, it was found that HY7801 can alleviate BV because it can suppress the expression of virulence factor genes of GV involved in epithelial cell adhesion and biofilm formation along with antibacterial activity against GV. These results indicate that HY7801 can be used as a promising probiotic strain for the maintenance of a healthy vaginal physiological state.

Bifidobacterium BLa80 mitigates colitis by altering gut microbiota and alleviating inflammation

This study was conducted to explore the therapeutic effect of the probiotic Bifidobacterium animalis subsp. lactis BLa80 on inflammatory bowel disease. A model of ulcerative colitis (UC) was induced in C57BL/6 mice by administering of 2.5% dextran sulphate sodium (DSS) for 8 days. After developing UC, some mice were treated via intragastric administration of BLa80 at a dose of 109 colony-forming units to assess the preventive effects of BLa80 on DSS-induced UC. Compared with non-treated UC model mice, BLa80-treated mice had reduced colon shortening and improvements in colonic tissue structure. Treatment with BLa80 also decreased the serum concentrations of the proinflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin (IL) 6 and IL-17 in mice. 16S rRNA gene sequencing revealed that BLa80 increased gut microbial diversity in mice and modulated UC-associated imbalances in the gut microbiota. BLa80 selectively promoted the growth of beneficial bacteria, including Romboutsia and Adlercreutzia, the abundances of which were negatively correlated with concentration of cellular inflammatory factors. In summary, the study results demonstrated that pretreatment with B. lactis BLa80 reduced intestinal inflammation and altered the gut microbiota, implying that BLa80 is a promising probiotic strain with potential therapeutic function in UC.

Complete Genome Sequence of Lactobacillus acidophilus LA-10A, a Promising Probiotic Strain Isolated from Fermented Mare's Milk.

ABSTRACTThis report describes the whole-genome sequence of Lactobacillus acidophilus LA-10A, isolated from fermented mare’s milk. This strain has been widely consumed due to its excellent performance in the treatment and prevention of Helicobacter pylori infection. The genome sequence of LA-10A provides further molecular information about its features.

Anti-allergic effects of two potential probiotic strains isolated from infant feces in China

• Infant feces-derived bacterial strains acted on the host differentially. • L. paracasei 207-27 showed stronger anti-allergic effects than LGG. • L. paracasei 207-27 characteristically enriched Lactobacillaceae in allergic host. • B. breve 207-1 showed potent immunomodulatory effects. Abnormal cross-talk between the intestinal microbiota of host animals and their immunity is evidently associated with an increase in the prevalence of allergy, and some selected probiotics have been found to play a role in pertinent mechanisms. Herein we evaluated the anti-allergic effects and mechanisms of two newly identified strains isolated from infant feces, namely Bifidobacterium breve 207-1 (207-1) and Lacticaseibacillus paracasei 207-27 (207-27), in ovalbumin-sensitized mice. We found that 207-27 showed stronger anti-allergic effects than 207-1 and even Lacticaseibacillus rhamnosus GG, which could be attributed to enhanced systemic and intestinal mucosal immunity, restored intestinal microbiome, and enriched Lactobacillaceae. In addition, 207-1 markedly enhanced splenic cytokine levels and partially restore microbial dysbiosis in allergic mice. To summarize, 207-27 and 207-1 could characteristically influence host immunity and intestinal microbiota in a strain-dependent manner. We believe that 207-27 is a promising probiotic strain considering its beneficial effects on the host.

Transcriptome analysis revealed growth phase-associated changes of a centenarian-originated probiotic Bifidobacterium animalis subsp. lactis A6

BackgroundThe physiology and application characteristics of probiotics are closely associated with the growth phase. Bifidobacterium animalis subsp. lactis A6 is a promising probiotic strain isolated from the feces of a healthy centenarian in China. In this study, RNA-seq was carried out to investigate the metabolic mechanism between the exponential and the stationary phase in B. lactis A6.ResultsDifferential expression analysis showed that a total of 815 genes were significantly changed in the stationary phase compared to the exponential phase, which consisted of 399 up-regulated and 416 down-regulated genes. The results showed that the transport and metabolism of cellobiose, xylooligosaccharides and raffinose were enhanced at the stationary phase, which expanded carbon source utilizing profile to confront with glucose consumption. Meanwhile, genes involved in cysteine-cystathionine-cycle (CCC) pathway, glutamate dehydrogenase, branched-chain amino acids (BCAAs) biosynthesis, and Clp protease were all up-regulated in the stationary phase, which may enhance the acid tolerance of B. lactis A6 during stationary phase. Acid tolerance assay indicated that the survival rate of stationary phase cells was 51.07% after treatment by pH 3.0 for 2h, which was 730-fold higher than that of 0.07% with log phase cells. In addition, peptidoglycan biosynthesis was significantly repressed, which is comparable with the decreased growth rate during the stationary phase. Remarkably, a putative gene cluster encoding Tad pili was up-regulated by 6.5 to 12.1-fold, which is consistent with the significantly increased adhesion rate to mucin from 2.38% to 4.90% during the transition from the exponential phase to the stationary phase.ConclusionsThis study reported growth phase-associated changes of B. lactis A6 during fermentation, including expanded carbon source utilizing profile, enhanced acid tolerance, and up-regulated Tad pili gene cluster responsible for bacterial adhesion in the stationary phase. These findings provide a novel insight into the growth phase associated characteristics in B. lactis A6 and provide valuable information for further application in the food industry.

Lacticaseibacillus paracasei K56 Attenuates High-Fat Diet-Induced Obesity by Modulating the Gut Microbiota in Mice.

This study investigated the effects of Lacticaseibacillus paracasei K56 (L. paracasei K56) on body weight, body composition, and glycolipid metabolism in mice with high-fat diet-induced obesity and explored the underlying mechanisms. Male C57BL/6J mice were fed a high-fat diet for 8 weeks to induce obesity; then, the obese mice were gavaged with or without L. paracasei K56 for 10 weeks. The body weight, body composition, fat mass, blood lipid, blood glucose, and hormones of the mice were evaluated. Moreover, the fatty acid synthesis (FAS) and peroxisome proliferator-activated receptor γ (PPAR-γ) expressions in the liver were detected via Western blotting. 16S rRNA gene sequencing was adopted to determine the gut microbiota alterations. The high-fat diet successfully induced obesity, as indicated by the abnormal increase in body weight, visceral fat, fat mass, blood lipids, fasting blood glucose, and insulin-resistance. Moreover, the FAS expression in the liver was significantly increased, whereas the PPAR-γ expression was significantly decreased. The relative abundance of Proteobacteria, Actinobacteria and Patescibacteria was also significantly increased, and that of Verrucomicrobia was significantly decreased. However, these indicators of mice supplemented with L. paracasei K56 were significantly opposite to those of obese mice. The Ruminococcuaceae_UCG-013, Akkermansia, Prevotellaceae_UCG-001, Muribaculum, and Lachnospiraceae_NK4A136 groups were significantly negatively correlated with body weight, blood lipids, and blood glucose-related indicators, whereas Coriobacteriaceae_UCG-002, Enterorhabdus, Raoultibacter, Acinetobacter, Romboutsia, Leuconostoc, and Erysipelatoclostridium were significantly positively correlated with these indicators. L. paracasei K56 might be a promising probiotic strain that could effectively slow down the body weight gain, reduce fat accumulation, alleviate insulin-resistance, and restore pancreatic β-cell function in obese mice by regulating the gut microbiota.

Draft Genome Sequence of Weissella cibaria P71, a Promising Aquaculture Probiotic Strain Isolated from Common Octopus (Octopus vulgaris).

ABSTRACTWeissella cibaria P71 is a lactic acid bacterium that was isolated from common octopus (Octopus vulgaris) and previously showed interesting probiotic properties for turbot (Scophthalmus maximus L.) farming. The draft genome sequence of this strain provides further data to support its potential as a probiotic for aquaculture.

Probiotics for the Management of Sepsis: Advances in Animal Models and Intensive Care Unit Environments

Sepsis frequently leads to multiple organ failure and is a major cause of morbidity and mortality in critically ill patients. Although intensive care protocols and antibiotic therapy have improved sepsis treatment, specific management is lacking with respect to efficient protection from tissue damage and long-term outcomes. Probiotics are live microbes that modulate the immune system and inflammation and colonize the gut. In this narrative review, we have traced the evolution of the administration of probiotics in an animal model of sepsis and treatment alternatives in the intensive care unit setting. First, probiotics are categorized by species before describing their modulation of the microbiota, repair of tissue-specific damage, immune response, and molecular pathways to prevent complications. The impact on therapy for infant and adult patients is also addressed. Finally, we have emphasized the challenges and gaps in current studies as well as future perspectives for further investigation. The present review can open up avenues for new strategies that employ promising probiotic strains for the treatment of sepsis and discusses their ability to prevent disease-associated long-term complications.

Natural Killer Cell Activation by Weissella cibaria JW15 Isolated from Kimchi

Natural killer (NK) cells are innate immune cells with the capacity to eliminate virus-infected and cancer cells. Therefore, enhancing NK cell activity remains a promising strategy to control viral infection and cancer development. Recent studies highlighted the immunostimulatory effect of lactic acid bacteria (LAB), especially via activation of NK cells. Among LAB, Weissella cibaria JW15, isolated from kimchi, activated splenocytes and enhanced immune responses, but whether JW15 enhanced NK cell activity was unclear. In this study, we investigated if JW15 affects NK cell activity and a possible role of exopolysaccharides (EPS) produced by JW15 in immune-stimulatory activity. Splenocytes or NK cells isolated from mice were treated with live JW15 or EPS, and then evaluated for cell surface levels of activation markers, intracellular levels of granzyme B and perforin, cytokine production, including IFN-γ, and cytotoxicity against tumor cells. Our results revealed that JW15 induced the activation of NK cells, as shown by increased NK cell cytotoxicity activity, as well as increased activation markers and IFN-γ production. In addition, EPS activated NK cells and splenocytes, leading to the secretion of various cytokines. Furthermore, oral administration of live JW15 increased NK cell cytotoxicity. Taken together, our findings suggest JW15 as a promising probiotic candidate strain with the immune-enhancing potential to prevent or treat viral infection and cancer.

<i>In Vitro</i> Characterization of Cell Surface Properties of 14 Vaginal <i>Lactobacillus</i> Strains as Potential Probiotics

Probiotics are live microorganisms which when administered in adequate amounts confer a health benefit on the host. Human-origin Lactobacillus is a preferable source of probiotic bacteria. This study screened 14 vaginal Lactobacillus strains as probiotic candidates by investigating probiotic-related cell surface characteristics including cell surface hydrophobicity (CSH), Lewis acidity/basicity, autoaggregation, and biofilm formation. Moderate to high CSH and autoaggregation, high basicity and low acidity were prevalent in the 14 tested strains. Biofilm formation varied in a large range among the 14 tested strains. CSH showed a high correlation with Lewis acidity and autoaggregation, while Lewis acidity was highly correlated with autoaggregation and biofilm formation. Four strains were selected as promising probiotic strains. This study was the first one to compare antibiotic sensitivity between biofilm-forming cells and planktonic cells of Lactobacillus species, and found that biofilm-forming cells of a L. fermentum strain had a significantly higher survival rate than planktonic cells in cefotaxime, cefmetazole and tetracycline, but were as sensitive to oxacillin and ampicillin as planktonic cells were.

Complete Genome Sequencing and Comparative Genomic Analysis of Streptococcus thermophilus CKDB027, a Promising Probiotic Bacterial Strain

Complete Genome Sequencing and Comparative Genomic Analysis of <i>Streptococcus thermophilus</i> CKDB027, a Promising Probiotic Bacterial Strain

Lactobacillus Plantarum 108 Inhibits Streptococcus mutans and Candida albicans Mixed-Species Biofilm Formation.

Streptococcus mutans is the principal biofilm forming oral pathogen associated with dental caries. Studies have shown that Candida albicans, a commensal oral fungus is capable of forming pathogenic mixed-species biofilms with S. mutans. The treatment of bacterial and fungal infections using conventional antimicrobial agents has become challenging due to the antimicrobial resistance of the biofilm mode of growth. The present study aimed to evaluate the efficacy of secretory components of Lactobacillus plantarum 108, a potentially promising probiotic strain, against S. mutans and C. albicans single and mixed-species biofilms. L. plantarum 108 supernatant inhibited S. mutans and C. albicans single-species biofilms as shown by XTT reduction assay, crystal violet assay, and colony forming units counting. The probiotic supernatant significantly inhibited the S. mutans and C. albicans mixed-species biofilm formation. The pre-formed mixed-species biofilms were also successfully reduced. Confocal microscopy showed poorly developed biofilm architecture in the probiotic supernatant treated biofilms. Moreover, the expression of S. mutans genes associated with glucosyltransferase activity and C. albicans hyphal specific genes (HWP1, ALS1 and ALS3) were down-regulated in the presence of the probiotic supernatant. Altogether, the data demonstrated the capacity of L. plantarum 108 supernatant to inhibit the S. mutans and C. albicans mixed-species biofilms. Herein, we provide a new insight on the potential of probiotic-based strategies to prevent bacterial-fungal mixed-species biofilms associated with dental caries.

Engineered Recombinant Escherichia coli Probiotic Strains Integrated with F4 and F18 Fimbriae Cluster Genes in the Chromosome and Their Assessment of Immunogenic Efficacy in Vivo.

F4 (K88) and F18 fimbriaed enterotoxigenic Escherichia coli (ETEC) are the predominant causes of porcine postweaning diarrhea (PWD), and vaccines are considered the most effective preventive approach against PWD. Since heterologous DNA integrated into bacterial chromosomes could be effectively expressed with stable inheritance, we chose probiotic EcNc (E. coli Nissle 1917 prototype cured of cryptic plasmids) as a delivery vector to express the heterologous F4 or both F4 and F18 fimbriae and sequentially assessed their immune efficacy of anti-F4 and F18 fimbriae in both murine and piglet models. Employing the CRISPR-cas9 technology, yjcS, pcadA, lacZ, yieN/trkD, maeB, and nth/tppB sites in the chromosome of an EcNc strain were targeted as integration sites to integrate F4 or F18 fimbriae cluster genes under the Ptet promotor to construct two recombinant integration probiotic strains (RIPSs), i.e., nth integration strain (EcNcΔnth/tppB::PtetF4) and multiple integration strain (EcNc::PtetF18x4::PtetF4x2). Expression of F4, both F4 and F18 fimbriae on the surfaces of two RIPSs, was verified with combined methods of agglutination assay, Western blot, and immunofluorescence microscopy. The recombinant strains have improved adherence to porcine intestinal epithelial cell lines. Mice and piglets immunized with the nth integration strain and multiple integration strain through gavage developed anti-F4 and both anti-F4 and anti-F18 IgG immune responses. Moreover, the serum antibodies from the immunized mice and piglets significantly inhibited the adherence of F4+ or both F4+ and F18+ ETEC wild-type strains to porcine intestinal cell lines in vitro, indicating the potential of RIPSs as promising probiotic strains plus vaccine candidates against F4+/F18+ ETEC infection.

Piacentinu Ennese PDO Cheese as Reservoir of Promising Probiotic Bacteria.

Piacentinu Ennese is a protected designation of origin (PDO) cheese produced in the surrounding area of Enna (Sicily, Italy), using raw ewe’s milk without the addition of any starter cultures. In the present study, the Lactobacillus population of Piacentinu Ennese PDO cheese was in vitro screened in order to select promising probiotic strains to be further used in humans. One hundred and sixty-nine lactic acid bacteria (LAB) were isolated from 90 days ripened cheeses and identified by Rep-PCR genomic fingerprinting, using the (GTG)5-primer, and by MALDI-TOF MS. One hundred and thirteen (113) isolates belonging to QPS-list species were characterized for both safety and functional properties. All tested isolates were considered safe because none showed either gelatinase, DNase, mucinase, or hemolytic activity. Tolerance to lysozyme, bile salts, and acidic conditions, along with ability to survive under simulated gastrointestinal digestion, were observed. In addition, based on antimicrobial activity against pathogens, cell surface characteristics, Caco-2 adhesion abilities, and anti-inflammatory potential, it was possible to confirm the strain-dependent functional aptitude, suggesting that Piacentinu Ennese PDO cheese may be considered a precious source of probiotic candidates.

Potential Properties of Lactobacillus plantarum F-10 as a Bio-control Strategy for Wound Infections.

In this study, Lactobacillus plantarum F-10, a promising probiotic strain isolated from fecal microbiota of healthy breastfed infant, was assessed as a bio-control strategy for wound infections. Pseudomonas aeruginosa PAO1/ATCC 27853, methicillin-resistant Staphylococcus aureus ATCC 43300, and their hospital-derived strains isolated from skin chronic wound samples were used as important skin pathogens. The cell-free extract (CFE) of the strain F-10 was shown to inhibit the growth of all pathogens tested, while no inhibition was observed when CFE was neutralized. The strain displayed no hemolysis and exhibited a strong auto-aggregating phenotype (51.48 ± 1.45%, 5h) as well as co-aggregation. Antibiotic resistance profile was found to be safe according to the European Food Safety Authority. Biofilm formation was measured by crystal violet assay and visualized with scanning electron microscopy and confocal laser scanning microscopy. One hundred percent reduction in biofilm formation of all pathogens tested was obtained by sub-MIC value (12.5mg/ml) of CFE following 24-h co-incubation. Inhibition of quorum sensing-controlled virulence factors (motility, protease and elastase activity, production of pyocyanin and rhamnolipid) of P. aeruginosa strains was also observed. DPPH radical scavenging activity of the CFE was determined as 88.57 ± 0.49%. In conclusion, our results suggest that L. plantarum F-10 may represent an alternative bio-control strategy against skin infections with its antimicrobial, anti-biofilm, anti-quorum sensing, and antioxidant activity.

Probiotics against airway allergy: host factors to consider.

ABSTRACTThe worldwide prevalence of allergic diseases has drastically increased in the past decades. Recent studies underline the importance of microbial exposure for the development of a balanced immune system. Consequently, probiotic bacteria are emerging as a safe and natural strategy for allergy prevention and treatment. However, clinical probiotic intervention studies have so far yielded conflicting results. There is increasing awareness about the importance of host-associated factors that determine whether an individual will respond to a specific probiotic treatment, and it is therefore crucial to promote a knowledge-based instead of an empirical selection of promising probiotic strains and their administration regimen.In this Review, we summarize the insights from animal model studies of allergic disease, which reveal how host-related factors – such as genetic makeup, sex, age and microbiological status – can impact the outcomes of preventive or curative probiotic treatment. We explore why and how these factors can influence the results of probiotic studies and negatively impact the reproducibility in animal experiments. These same factors might profoundly influence the outcomes of human clinical trials, and can potentially explain the conflicting results from probiotic intervention studies. Therefore, we also link these host-related factors to human probiotic study outcomes in the context of airway allergies.

Carotenoid producing Bacillus aquimaris found in chicken gastrointestinal tracts

Pigmented spore-forming bacterial strains were isolated from the gastrointestinal tracts of chickens for screening for heat-stable carotenoid-producing strains that could be applied as feed supplements. Of the seven heat-stable pigmented isolates screened, only two, yellow Sporosarcina saromensis CH1 and red-orange Bacillus aquimaris CH9, produced pigments with typical carotenoid absorbance peaks (400–500 nm). The CH9 carotenoids exhibited higher scavenging activity (73.2%) of DPPH free radicals than the CH1 carotenoids (35.9%) and carotenoids of the reference B. indicus HU36 strain (78.4%), in comparison to 100% activity of acid ascorbic at 18.75 M as the standard. The CH9 strain produced high levels of carotenoids (439 g [g DW]-1) and formed nearly 100% spores, whereas the CH1 strain produced low levels of carotenoids (92 g [g DW]-1) and only achieved 30% sporulation. Chromatographic and spectral profiles of the carotenoids found in CH9 indicated the presence of as many as 11 different carotenoid types closely related to 1-HO-demethylspheroidene and keto/hydroxyl derivatives of  carotene. We successfully produced concentrated orange CH9 spore powder at a high concentration of 6.1 × 1011 CFU g-1; these spores were much more heat-stable (66% survival at 80°C for 20 min) than the reference B. indicus HU36 spores (9% survival at 50°C for 20 min). In conclusion, B. aquimaris CH9 is a promising probiotic carotenoid-producing strain, with heat-stable spores that should withstand the heat-treatment processing required for feed and food supplement production.

Functional Characterization of Probiotic Potential of Novel Pigmented Bacterial Strains for Aquaculture Applications.

The bioprospecting proficient of novel pigmented probiotic strains with respect to aquaculture industry was unexplored hitherto. In this study, we investigated the probiotic potential of novel pigmented bacterial strains isolated from the indigenous soil sediments in their vicinal habitats, which were screened for their antimicrobial activity against aquatic pathogens using agar well diffusion assay. The strains namely Exiguobacterium acetylicum (S01), Aeromonas veronii (V03), and Chryseobacterium joostei (V04) were phenotypically identified and confirmed by 16S rRNA gene sequence analysis. Further characterization revealed that strains S01 and V03 survive relatively in lower pH and higher bile salt concentrations and possess good adherence ability and broad-spectrum antibiotic susceptibility. The isolate S01 exhibited the higher adhesion ability to hydrocarbons (82%) and mannose-specific adhesion (msa) gene expression. Additionally, the probiotic effects were evaluated in Artemia nauplii fed with algae supplemented with S01, V03, and V04 strains (2.7 × 107cfu/mL) for 3days under axenic environment. We observed a significant increase (p < 0.05) in the survival rate of Artemia nauplii treated with S01 (83 ± 5%) and V03 (55 ± 5%), whereas the survival rate was only 30 ± 0% in the untreated group. Moreover, the individual length (IL) was increased in treated group S01 (156.7 ± 2.2μm), V03 (146.1 ± 3.4μm), and V04 (134.4 ± 2.5μm) compared with untreated group (116.0 ± 4.8μm). Our results revealed that E. acetylicum S01 exhibits desirable functional probiotic attributes compared to A. veronii and C. joostei and it would be a promising probiotic strain, which can be efficiently used in the aquaculture applications.

How to routinely assess transition, adhesion and survival of probiotics into the gut: a case study on propionibacteria

SummaryTwo commercial promising probiotic strains (Propionibacterium jensenii and Propionibacterium freudenreichii) were studied to evaluate two basic probiotic requisites (adhesion and survival during the transit into the gut); two commercial starter cultures (Lactobacillus plantarum and Lactobacillus delbrueckii subsp. bulgaricus) were used as references. As an additional goal, the technological robustness was evaluated as growth as a function of pH, temperature and salt. Adhesion was studied as biofilm formation and hydrophobicity, whereas a simplified protocol was used to simulate the transit into the gut, along with the assessment of survival at pH 2.5 and in the presence of 0.3% bile salts. Propionibacteria were hydrophobic and form biofilm on glass slides, thus confirming the correlation of these properties and with the ability to adhere. None of the strains survived after the simulation of the transit into the gut, but this property could be induced in propionibacteria using a simple protocol of adaptive evolution. This paper suggests the possibility of using hydrophobicity as a screening tool to assess adhesion in propionibacteria and highlights the necessity of using a complete protocol of simulation of the gut to study the resistance to the conditions of stomach and intestine to avoid false‐positive results.