Probiotics for Prevention and Treatment of Clostridium difficile Infection.

Probiotics have been claimed as a valuable tool to restore the balance in the intestinal microbiota following a dysbiosis caused by, among other factors, antibiotic therapy. This perturbed environment could favor the overgrowth of Clostridium difficile, and in fact, the occurrence of C. difficile-associated infections (CDI) is increasing in recent years. In spite of the high number of probiotics able to in vitro inhibit the growth and/or toxicity of this pathogen, its application for treatment or prevention of CDI is still scarce since there are not enough well-defined clinical studies supporting efficacy. Only a few strains, such as Lactobacillus rhamnosus GG and Saccharomyces boulardii, have been studied in more extent. The increasing knowledge about the probiotic mechanisms of action against C. difficile, some of them reviewed here, makes promising the application of these live biotherapeutic agents against CDI. Nevertheless, more effort must be paid to standardize the clinical studies conducted to evaluate probiotic products, in combination with antibiotics, in order to select the best candidate for C. difficile infections.

Engineering a Lysin with Intrinsic Antibacterial Activity (LysMK34) by Cecropin A Fusion Enhances Its Antibacterial Properties against Acinetobacter baumannii.

Bacteriophage-encoded lysins are increasingly reported as alternatives to combat Acinetobacter baumannii infections, for which limited therapeutic options are available. Some lysins, such as LysMK34, have a C-terminal amphipathic helix allowing them to penetrate the otherwise-impermeable outer membrane barrier. Another approach to kill Gram-negative pathogens with lysins relies on fusion of a peptide with outer membrane-permeabilizing properties to the lysin. In this work, we aimed to leverage the intrinsic antibacterial activity of LysMK34 by fusing the peptide cecropin A to its N terminus via a linker of three Ala-Gly repeats, resulting in engineered LysMK34 (eLysMK34). The engineered lysin has an improved antibacterial activity compared to that of the parental lysin, LysMK34, in terms of MICs (0.45 to 1.2 µM), killing rate, and killing extent. eLysMK34 has a ≥2-fold-increased activity against stationary-phase cells, and the bactericidal effect becomes less dependent on the intracellular osmotic pressure. In particular, colistin-resistant strains become highly susceptible to eLysMK34, and enhanced antibacterial activity is observed in complement-deactivated human serum. These observations demonstrate that fusion of a lysin with intrinsic antibacterial activity with a selected outer membrane-permeabilizing peptide is a useful strategy to further improve the in vitro antibacterial properties of such lysins. IMPORTANCE Phage lysins are a new class of enzyme-based antibiotics that increasingly gain interest. Lysins kill cells through rapid degradation of the peptidoglycan layer, resulting in sudden osmotic lysis. Whereas Gram-positive bacteria are readily susceptible to the actions of lysins, Gram-negative bacteria are naturally resistant, as the outer membrane protects their peptidoglycan layer. This work reveals that fusing an outer membrane-permeabilizing peptide to a lysin with intrinsic antibacterial activity results in a superior lysin that shows improved robustness in its antibacterial activity, including against the most worrisome colistin-resistant A. baumannii strains.

Functional bacterial cultures for dairy applications: Towards improving safety, quality, nutritional and health benefit aspects.

Traditionally, fermentation was used to preserve the shelf life of food. Currently, in addition to favouring food preservation, well standardized and controlled industrial processes are also aimed at improving the functional characteristics of the final product. In this regard, starter cultures have become an essential cornerstone of food production. The selection of robust microorganisms, well adapted to the food environment, has been followed by the development of microbial consortia that provide some functional characteristics, beyond their acidifying capacity, achieving safer, high-quality foods with improved nutritional and health-promoting properties. In addition to starters, adjunct cultures and probiotics, which normally do not have a relevant role in fermentation, are added to the food in order to provide some beneficial characteristics. This review focuses on highlighting the functional characteristics of food starters, as well as adjunct and probiotic cultures (mainly lactic acid bacteria and bifidobacteria), with a specific focus on the synthesis of metabolites for preservation and safety aspects (e.g. bacteriocins), organoleptic properties (e.g. exopolysaccharides), nutritional (e.g. vitamins) and health improvement (e.g. neuroactive molecules). Literature reporting the application of these functional cultures in the manufacture of foods, mainly those related to dairy production, such as cheeses and fermented milks, has also been updated.

Novel methods of microbiome analysis in the food industry.

The study of the food microbiome has gained considerable interest in recent years, mainly due to the wide range of applications that can be derived from the analysis of metagenomes. Among these applications, it is worth mentioning the possibility of using metagenomic analyses to determine food authenticity, to assess the microbiological safety of foods thanks to the detection and tracking of pathogens, antibiotic resistance genes and other undesirable traits, as well to identify the microorganisms responsible for food processing defects. Metataxonomics and metagenomics are currently the gold standard methodologies to explore the full potential of metagenomes in the food industry. However, there are still a number of challenges that must be solved in order to implement these methods routinely in food chain monitoring, and for the regulatory agencies to take them into account in their opinions. These challenges include the difficulties of analysing foods and food-related environments with a low microbial load, the lack of validated bioinformatics pipelines adapted to food microbiomes and the difficulty of assessing the viability of the detected microorganisms. This review summarizes the methods of microbiome analysis that have been used, so far, in foods and food-related environments, with a specific focus on those involving Next-Generation Sequencing technologies.

Lysin LysMK34 of Acinetobacter baumannii Bacteriophage PMK34 Has a Turgor Pressure-Dependent Intrinsic Antibacterial Activity and Reverts Colistin Resistance.

The prevalence of extensively and pandrug-resistant strains of Acinetobacter baumannii leaves little or no therapeutic options for treatment for this bacterial pathogen. Bacteriophages and their lysins represent attractive alternative antibacterial strategies in this regard. We used the extensively drug-resistant A. baumannii strain MK34 to isolate the bacteriophage PMK34 (vB_AbaP_PMK34). This phage shows fast adsorption and lacks virulence genes; nonetheless, its narrow host spectrum based on capsule recognition limits broad application. PMK34 is a Fri1virus member of the Autographiviridae and has a 41.8-kb genome (50 open reading frames), encoding an endolysin (LysMK34) with potent muralytic activity (1,499.9 ± 131 U/µM), a typical mesophilic thermal stability up to 55°C, and a broad pH activity range (4 to 10). LysMK34 has an intrinsic antibacterial activity up to 4.8 and 2.4 log units for A. baumannii and Pseudomonas aeruginosa strains, respectively, but only when a high turgor pressure is present. The addition of 0.5 mM EDTA or application of an osmotic shock after treatment can compensate for the lack of a high turgor pressure. The combination of LysMK34 and colistin results in up to 32-fold reduction of the MIC of colistin, and colistin-resistant strains are resensitized in both Mueller-Hinton broth and 50% human serum. As such, LysMK34 may be used to safeguard the applicability of colistin as a last-resort antibiotic.IMPORTANCEA. baumannii is one of the most challenging pathogens for which development of new and effective antimicrobials is urgently needed. Colistin is a last-resort antibiotic, and even colistin-resistant A. baumannii strains exist. Here, we present a lysin that sensitizes A. baumannii for colistin and can revert colistin resistance to colistin susceptibility. The lysin also shows a strong, turgor pressure-dependent intrinsic antibacterial activity, providing new insights in the mode of action of lysins with intrinsic activity against Gram-negative bacteria.

In Vitro Evaluation of Different Prebiotics on the Modulation of Gut Microbiota Composition and Function in Morbid Obese and Normal-Weight Subjects.

The gut microbiota remains relatively stable during adulthood; however, certain intrinsic and environmental factors can lead to microbiota dysbiosis. Its restoration towards a healthy condition using best-suited prebiotics requires previous development of in vitro models for evaluating their functionality. Herein, we carried out fecal cultures with microbiota from healthy normal-weight and morbid obese adults. Cultures were supplemented with different inulin-type fructans (1-kestose, Actilight, P95, Synergy1 and Inulin) and a galactooligosaccharide. Their impact on the gut microbiota was assessed by monitoring gas production and evaluating changes in the microbiota composition (qPCR and 16S rRNA gene profiling) and metabolic activity (gas chromatography). Additionally, the effect on the bifidobacterial species was assessed (ITS-sequencing). Moreover, the functionality of the microbiota before and after prebiotic-modulation was determined in an in vitro model of interaction with an intestinal cell line. In general, 1-kestose was the compound showing the largest effects. The modulation with prebiotics led to significant increases in the Bacteroides group and Faecalibacterium in obese subjects, whereas in normal-weight individuals, substantial rises in Bifidobacterium and Faecalibacterium were appreciated. Notably, the results obtained showed differences in the responses among the tested compounds but also among the studied human populations, indicating the need for developing population-specific products.

Exopolysaccharides synthesized by Bifidobacterium animalis subsp. lactis interact with TLR4 in intestinal epithelial cells.

The toll-like receptors involved in recognition of the exopolysaccharide produced by two isogenic, ropy and non-ropy, Bifidobacterium animalis subsp. lactis strains were investigated. Both strains interact with human embryonic kidney (HEK)-293 cells via TLR2, whereas purified EPSs specifically stimulate TLR4 regardless their molar mass.

Bioactive compounds from regular diet and faecal microbial metabolites.

PURPOSE: Short-chain fatty acids (SCFAs) formation by intestinal bacteria is regulated by many different factors, among which dietary fibre is currently receiving most attention. However, since fibre-rich foods are usually good dietary sources of phenolic compounds, which are also known to affect the microbiota, authors hypothesize that the regular intake of these bioactive compounds could be associated with a modulation of faecal SCFA production by the intestinal microbiota. METHODS: In this work, food intake was recorded by means of a validated Food Frequency Questionnaire. Fibres were determined using Marlett food composition tables, and phenolic compounds were obtained from Phenol-Explorer Database. Analysis of SCFA was performed by gas chromatography-flame ionization/mass spectrometry and quantification of microbial populations in faeces by quantitative PCR. RESULTS: Klason lignin and its food contributors, as predictors of faecal butyrate production, were directly associated with Bacteroides and Bifidobacterium levels, as well as lignans with Bacteroides. Also, anthocyanidins, provided by strawberries, were associated with faecal propionate and inversely related to Lactobacillus group. CONCLUSIONS: These results support the hypothesis we put forward regarding the association between some vegetable foods (strawberries, pasta, lentils, lettuce and olive oil) and faecal SCFA. More studies are needed in order to elucidate whether these associations have been mediated by the bacterial modulatory effect of the bioactive compounds, anthocyanins, lignans or Klason lignin, present in foodstuffs.

Probiotics for Prevention and Treatment of Clostridium difficile Infection.

Probiotics have been claimed as a valuable tool to restore the balance in the intestinal microbiota following a dysbiosis caused by, among other factors, antibiotic therapy. This perturbed environment could favor the overgrowth of Clostridium difficile and, in fact, the occurrence of C. difficile-associated infections (CDI) is being increasing in recent years. In spite of the high number of probiotics able to in vitro inhibit the growth and/or toxicity of this pathogen, its application for treatment or prevention of CDI is still scarce since there are not enough well-defined clinical studies supporting efficacy. Only a few strains, such as Lactobacillus rhamnosus GG and Saccharomyces boulardii have been studied in more extent. The increasing knowledge about the probiotic mechanisms of action against C. difficile, some of them reviewed here, makes promising the application of these live biotherapeutic agents against CDI. Nevertheless, more effort must be paid to standardize the clinical studied conducted to evaluate probiotic products, in combination with antibiotics, in order to select the best candidate for C. difficile infections.

Bacterial diversity of the Colombian fermented milk "Suero Costeño" assessed by culturing and high-throughput sequencing and DGGE analysis of 16S rRNA gene amplicons.

"Suero Costeño" (SC) is a traditional soured cream elaborated from raw milk in the Northern-Caribbean coast of Colombia. The natural microbiota that characterizes this popular Colombian fermented milk is unknown, although several culturing studies have previously been attempted. In this work, the microbiota associated with SC from three manufacturers in two regions, "Planeta Rica" (Córdoba) and "Caucasia" (Antioquia), was analysed by means of culturing methods in combination with high-throughput sequencing and DGGE analysis of 16S rRNA gene amplicons. The bacterial ecosystem of SC samples was revealed to be composed of lactic acid bacteria belonging to the Streptococcaceae and Lactobacillaceae families; the proportions and genera varying among manufacturers and region of elaboration. Members of the Lactobacillus acidophilus group, Lactocococcus lactis, Streptococcus infantarius and Streptococcus salivarius characterized this artisanal product. In comparison with culturing, the use of molecular in deep culture-independent techniques provides a more realistic picture of the overall bacterial communities residing in SC. Besides the descriptive purpose, these approaches will facilitate a rational strategy to follow (culture media and growing conditions) for the isolation of indigenous strains that allow standardization in the manufacture of SC.

Bacteroides fragilis metabolises exopolysaccharides produced by bifidobacteria.

BACKGROUND: Bacteroides fragilis is the most frequent species at the human intestinal mucosal surface, it contributes to the maturation of the immune system although is also considered as an opportunistic pathogen. Some Bifidobacterium strains produce exopolysaccharides (EPS), complex carbohydrate polymers that promote changes in the metabolism of B. fragilis when this microorganism grows in their presence. To demonstrate that B. fragilis can use EPS from bifidobacteria as fermentable substrates, purified EPS fractions from two strains, Bifidobacterium longum E44 and Bifidobacterium animalis subsp. lactis R1, were added as the sole carbon source in cultures of B. fragilis DSMZ 2151 in a minimal medium. Bacterial counts were determined during incubation and the evolution of organic acids, short chain fatty acids (SCFA) and evolution of EPS fractions was analysed by chromatography. RESULTS: Growth of B. fragilis at early stages of incubation was slower in EPS than with glucose, microbial levels remaining higher in EPS at prolonged incubation times. A shift in metabolite production by B. fragilis occurred from early to late stages of growth, leading to the increase in the production of propionate and acetate whereas decrease lactate formation. The amount of the two peaks with different molar mass of the EPS E44 clearly decreased along incubation whereas a consumption of the polymer R1 was not so evident. CONCLUSIONS: This report demonstrates that B. fragilis can consume some EPS from bifidobacteria, with a concomitant release of SCFA and organic acids, suggesting a role for these biopolymers in bacteria-bacteria cross-talk within the intestine.

Exopolysaccharides Produced by Lactic Acid Bacteria and Bifidobacteria as Fermentable Substrates by the Intestinal Microbiota.

The functional food market, including products formulated to maintain a "healthy" gut microbiota, i.e. probiotics and prebiotics, has increased enormously since the end of the last century. In order to favor the competitiveness of this sector, as well as to increase our knowledge of the mechanisms of action upon human health, new probiotic strains and prebiotic substrates are being studied. This review discusses the use of exopolysaccharides (EPS), both homopolysaccharides (HoPS) and heteropolysaccharides (HePS), synthesized by lactic acid bacteria and bifidobacteria as potential prebiotics. These extracellular carbohydrate polymers synthesized by some gut inhabitants seem to be resistant to gastrointestinal digestion; these are susceptible as well to biodegradability by the intestinal microbiota depending on both the physicochemical characteristics of EPS and the pool of glycolytic enzymes harbored by microbiota. Therefore, although the chemical composition of these HoPS and HePS is different, both can be fermentable substrates by intestinal inhabitants and good candidates as prebiotic substrates. However, there are limitations for their use as additives in the food industry due to, on the one hand, their low production yield and, on the other hand, a lack of clinical studies demonstrating the functionality of these biopolymers.

Exopolysaccharide production and ropy phenotype are determined by two gene clusters in putative probiotic strain Lactobacillus paraplantarum BGCG11.

Lactobacillus paraplantarum BGCG11, a putative probiotic strain isolated from a soft, white, artisanal cheese, produces a high molecular-weight heteropolysaccharide, exopolysaccharide (EPS)-CG11, responsible for the ropy phenotype and immunomodulatory activity of the strain. In this study, a 26.4-kb region originating from the pCG1 plasmid, previously shown to be responsible for the production of EPS-CG11 and a ropy phenotype, was cloned, sequenced, and functionally characterized. In this region 16 putative open reading frames (ORFs), encoding enzymes for the production of EPS-CG11, were organized in specific loci involved in the biosynthesis of the repeat unit, polymerization, export, regulation, and chain length determination. Interestingly, downstream of the eps gene cluster, a putative transposase gene was identified, followed by an additional rfb gene cluster containing the rfbACBD genes, the ones most probably responsible for dTDP-L-rhamnose biosynthesis. The functional analysis showed that the production of the high-molecular-weight fraction of EPS-CG11 was absent in two knockout mutants, one in the eps and the other in the rfb gene cluster, as confirmed by size exclusion chromatography analysis. Therefore, both eps and rfb genes clusters are prerequisites for the production of high-molecular-weight EPS-CG11 and for the ropy phenotype of strain L. paraplantarum BGCG11.

A single mutation in the gene responsible for the mucoid phenotype of Bifidobacterium animalis subsp. lactis confers surface and functional characteristics.

Exopolysaccharides (EPS) are extracellular carbohydrate polymers synthesized by a large variety of bacteria. Their physiological functions have been extensively studied, but many of their roles have not yet been elucidated. We have sequenced the genomes of two isogenic strains of Bifidobacterium animalis subsp. lactis that differ in their EPS-producing phenotype. The original strain displays a nonmucoid appearance, and the mutant derived thereof has acquired a mucoid phenotype. The sequence analysis of their genomes revealed a nonsynonymous mutation in the gene Balat_1410, putatively involved in the elongation of the EPS chain. By comparing a strain from which this gene had been deleted with strains containing the wild-type and mutated genes, we were able to show that each strain displays different cell surface characteristics. The mucoid EPS synthesized by the strain harboring the mutation in Balat_1410 provided higher resistance to gastrointestinal conditions and increased the capability for adhesion to human enterocytes. In addition, the cytokine profiles of human peripheral blood mononuclear cells and ex vivo colon tissues suggest that the mucoid strain could have higher anti-inflammatory activity. Our findings provide relevant data on the function of Balat_1410 and reveal that the mucoid phenotype is able to alter some of the most relevant functional properties of the cells.

Red wine consumption is associated with fecal microbiota and malondialdehyde in a human population.

OBJECTIVES: Red wine intake has been associated with a lower risk of cardiovascular disease; its polyphenol content is the primary cause of antioxidant and anti-inflammatory properties attributed to this beverage. However, the way in which these activities are exerted is not yet clear, although some authors have proposed that intestinal microbiota could be implicated. METHODS: The association between red wine intake, inflammation, and oxidative stress parameters and fecal microbial populations has been explored in 38 adult volunteers. Food intake was recorded by means of an annual food frequency questionnaire (FFQ). Energy, cholesterol, and ethanol intake were analyzed using the nutrient Food Composition Tables developed by Centro de Enseñanza Superior de Nutrición y Dietética (CESNID) and polyphenol intake was obtained from the Phenol-Explorer Database. Fecal levels of Akkermansia, Bacteroides, Bifidobacterium, Blautia coccoides group, Clostridium leptum group, Lactobacillus group, and Faecalibacterium prausnitzii were determined by quantitative polymerase chain reaction. Serum concentrations of C-reactive protein (CRP), malondialdehyde (MDA), total antioxidant capacity (TAC), cholesterol, triglycerides and glucose were analyzed by standard methods. RESULTS: Subjects with regular consumption of red wine (mean = 100 ml/day) had lower serum concentrations of MDA and lower fecal levels of B. coccoides, C. leptum, Bifidobacterium, and Lactobacillus. A positive association between MDA levels and B. coccoides and Lactobacillus was also found. CONCLUSION: Regular consumption of red wine appears to be associated with a reduced serum lipoperoxidation in which the intestinal microbiota may be involved.

Genomic overview and biological functions of exopolysaccharide biosynthesis in Bifidobacterium spp.

For many years, bacterial exopolysaccharides (EPS) have received considerable scientific attention, mainly due to their contribution to biofilm formation and, above all, because EPS are potential virulence factors. In recent times, interest in EPS research has enjoyed a welcome boost thanks to the discovery of their ability to mediate communication processes with their surrounding environment and to their contribution to host health maintenance. In this review, we provide a fresh perspective on the genetics and activity of these polymers in members of the Bifidobacterium genus, a common gut inhabitant of humans and animals that has been associated with several health-promoting effects. Bifidobacteria can use EPS to protect themselves against the harsh conditions of the gastrointestinal tract, thus improving their persistence in the host. Indeed, the relevant function of EPS for bifidobacteria is underlined by the fact that most genomes sequenced until now contain genes related to EPS biosynthesis. A high interspecies variability in the number of genes and structural organization is denoted among species/subspecies; thus, eps clusters in this genus do not display a consensus genetic architecture. Their different G+C content compared to that of the whole genome suggests that eps genes have been acquired by horizontal transfer. From the host perspective, EPS-producing bifidobacteria are able to trigger both innate and adaptive immune responses, and they are able to modulate the composition and activity of the gut microbiota. Thus, these polymers seem to be critical in understanding the physiology of bifidobacteria and their interaction with the host.

Bifidobacterium bifidum PRL2010 modulates the host innate immune response.

Here, we describe data obtained from transcriptome profiling of human cell lines and intestinal cells of a murine model upon exposure and colonization, respectively, with Bifidobacterium bifidum PRL2010. Significant changes were detected in the transcription of genes that are known to be involved in innate immunity. Furthermore, results from enzyme-linked immunosorbent assays (ELISAs) showed that exposure to B. bifidum PRL2010 causes enhanced production of interleukin 6 (IL-6) and IL-8 cytokines, presumably through NF-κB activation. The obtained global transcription profiles strongly suggest that Bifidobacterium bifidum PRL2010 modulates the innate immune response of the host.

Exopolysaccharide-producing Bifidobacterium animalis subsp. lactis strains and their polymers elicit different responses on immune cells from blood and gut associated lymphoid tissue.

The effect of exopolysaccharide (EPS) producing bifidobacteria, and the EPS derived thereof, on the modulation of immune response was evaluated. Cells isolated from gut associated lymphoid tissue (GALT) and from peripheral blood mononuclear cells (PBMC) of naïve rats were used. The proliferation and cytokine production of these immune cells in the presence of the three isogenic Bifidobacterium animalis subsp. lactis strains (A1, A1dOx and A1dOxR), as well as their purified polymers, were in vitro analysed. The cytokine pattern produced by immune cells isolated from GALT showed that most levels remained stable in the presence of the three strains or their corresponding polymers. However, in PBMC the UV-inactivated bacteria induced higher levels of the ratios IFNγ/IL-17, TNFα/IL-10 and TNFα/TGFß, and no variation in the ratio IFNγ/IL-4. Thus, B. animalis subsp. lactis strains were able to activate blood monocytes as well as T lymphocytes towards a mild inflammatory Th1 response. Furthermore, only the EPS-A1dOxR was able to stimulate a response in a similar way than its EPS-producing bacterium. Our work supports the notion that some bifidobacterial EPS could play a role in mediating the dialog of these microorganisms with the immune system. In addition, this study emphasizes the effect that the origin of the immune cells has in results obtained; this could explain the great amount of contradiction found in literature about the immunomodulation capability of EPS from probiotic bacteria.

Mouse intestinal microbiome modulation by oral administration of a GABA-producing Bifidobacterium adolescentis strain.

IMPORTANCE: The gut microbiome-brain communication signaling has emerged in recent years as a novel target for intervention with the potential to ameliorate some conditions associated with the central nervous system. Hence, probiotics with capacity to produce neurotransmitters, for instance, have come up as appealing alternatives to treat disorders associated with disbalanced neurotransmitters. Herein, we further deep into the effects of administering a gamma-aminobutyric acid (GABA)-producing Bifidobacterium strain, previously demonstrated to contribute to reduce serum glutamate levels, in the gut microbiome composition and metabolic activity in a mouse model. Our results demonstrate that the GABA-producing strain administration results in a specific pattern of gut microbiota modulation, different from the one observed in animals receiving non-GABA-producing strains. This opens new avenues to delineate the specific mechanisms by which IPLA60004 administration contributes to reducing serum glutamate levels and to ascertain whether this effect could exert health benefits in patients of diseases associated with high-glutamate serum concentrations.

Probiotic Characteristics of Lactiplantibacillus plantarum CECT 9435 and Its Survival and Competitive Properties Under Simulated Conditions of the Child Gut Microbiota.

Probiotics are valuable microorganisms effective in reducing malnutrition-related infections in children. In this work, a collection of lactobacilli strains representative of traditional Andean fermented beverages was in vitro screened for their capability to survive the gastrointestinal transit, to adhere to the intestinal epithelium and to compete under simulated conditions of the child gut microbiota. The results allowed the selection of the riboflavin overproducing strain Lactiplantibacillus plantarum CECT 9435 based on its good rate of survival under in vitro gastrointestinal conditions when included in a food matrix representing the fortified food supplement Incaparina. The strain also showed good adhesion to HT29 cells producing mucus and outstanding performance in E. coli competition for the adhesion to this epithelial cell line. L. plantarum CECT 9435 gut performance was also evaluated in the child intestinal microbiota simulated in a dynamic gut model (BFBL simulator). The viability of the probiotic candidate in the gut conditions was high during the 7-day intervention period, reaching over 1 × 107 counts in each of the reactors simulating the three colonic regions. The transient viability of L. plantarum CECT 9435 within the child gut microbiota and its adhesion capacity to intestinal cells could facilitate the strain potential benefits as probiotic added to fortified supplementary foods destined to malnourished children.