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Inhibitory effect of probiotic Escherichia coli strain Nissle 1917 on adhesion to and invasion of intestinal epithelial cells by adherent-invasive E. coli strains isolated from patients with Crohn's disease.

BACKGROUND: Pathogenic adherent-invasive Escherichia coli have been isolated from ileal lesions of Crohn's disease. AIM: : To investigate the non-pathogenic E. coli strain Nissle 1917 (Mutaflor) as possible maintenance therapy in inflammatory bowel disease by testing its ability to prevent adherent-invasive E. coli strains from adhering to and invading human intestinal epithelial cells in vitro. METHODS: Bacterial adhesion to and invasion of intestinal epithelial cells (Intestine-407) were assessed by counting the colony-forming units. The inhibitory effect of E. coli Nissle 1917 was determined after co-incubation with adherent-invasive E. coli strains or after pre-incubation of the intestinal epithelial cells with this probiotic strain prior to infection with adherent-invasive E. coli strains. RESULTS: Strain Nissle 1917 exhibited dose- and time-dependent adherence to intestinal epithelial cells and inhibited the adhesion and invasion of various adherent-invasive E. coli strains. In co-infection experiments, the inhibitory effect on adherent-invasive E. coli adhesion reached 78-99.9%. Pre-incubation of intestinal epithelial cells with strain Nissle 1917 reduced adherent-invasive E. coli adhesion by 97.2-99.9%. The inhibitory effect on adherent-invasive E. coli invasion paralleled that on adhesion. CONCLUSION: As strong and significant inhibitory effects on adherent-invasive E. coli adhesion and invasion were observed in co-infection and pre-infection experiments, E. coli Nissle 1917 could be efficient for preventive or curative probiotic therapy in patients with Crohn's disease.

Bacterial Adhesion↗

Human ileostomy glycoproteins as a model for small intestinal mucus to investigate adhesion of probiotics.

Human ileostomy glycoproteins were used as a model for small intestinal mucus to investigate the adhesion of 12 Lactobacillus strains, one Lactococcus strain and one Propionibacterium strain, Both probiotic and dairy strains were tested. Adhesive and non-adhesive Escherichia coli strains were used as controls. All the strains were also tested for their adhesion to polystyrene. Adhesion to ileostomy glycoproteins and to polystyrene varied significantly among the strains tested. Lactobacillus rhamnosus (human isolate), Lactobacillus GG, Lact. acidophilus 1 and P. freudenreichii adhered to ileostomy glycoproteins. Adhesion was concentration-dependent and the most adhesive strains were able to saturate the substratum. These results indicate that human ileostomy glycoproteins can be used as a model system to select potential probiotic strains to complement the adhesion test with intestinal cell lines.

Bacterial Adhesion↗

Exclusion of vanA, vanB and vanC type glycopeptide resistance in strains of Lactobacillus reuteri and Lactobacillus rhamnosus used as probiotics by polymerase chain reaction and hybridization methods.

Strains of Lactobacillus reuteri and Lact. rhamnosus are used as probiotics in man and animal. The aim of this study was to determine whether the glycopeptide resistance in these lactobacilli has a similar genetic basis as in enterococci. Five Lact. reuteri strains and one Lact. rhamnosus, as well as four Enterococcus control strains, were probed for the vanA gene cluster, the vanB gene and the vanC gene by PCR and Southern hybridization, and DNA/DNA hybridization. Their resistance and plasmid patterns were also investigated. All Lactobacillus strains were resistant to vancomycin but susceptible to a broad range of antibiotics. Four of the Lactobacillus strains (including the Lact. rhamnosus strain) did not harbour any plasmid and two of them contained five and 6 plasmid bands respectively. None of the Lactobacillus strains possessed the vanA, vanB or vanC gene. These findings indicate that the glycopeptide resistance of the Lactobacillus strains analysed is different from the enterococcal type. The study provides reassurance on the safety of the Lactobacillus strains used as probiotics with regard to their vancomycin resistance.

Anti-Bacterial Agents↗

Partial characterization of a bacteriocin produced by Lactobacillus delbrueckii subsp. lactis UO004, an intestinal isolate with probiotic potential.

AIMS: The partial characterization of a bacteriocin produced by a human Lactobacillus delbrueckii isolate with probiotic potential. METHODS AND RESULTS: A bacterocin, UO004, was partially purified by cation exchange followed by a hydrophobic interaction column, biochemically characterized and the N-terminal region sequenced. Bacteriocin UO004 was found to be a hydrophobic, heat-stable polypeptide with an apparent molecular mass of 6 kDa. It was also stable and active over a wide pH range. CONCLUSION: The active compound was proteinaceous, heat-stable, and had a bactericidal (and bacteriolytic) mode of action on a limited number of micro-organisms. Such a narrow spectrum of activity is typical for bacteriocins produced by intestinal Lactobacillus. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacteriocin UO004 from a probiotic strain is a new compound that does not share any homology with any other known lactic acid bacteria bacteriocin. Furthermore, Lact. delbrueckii is regarded as a suitable starter for the production of fermented milks.

Animals↗

Growth studies of potentially probiotic lactic acid bacteria in cereal-based substrates.

AIMS: The overall growth kinetics of four potentially probiotic strains (Lactobacillus fermentum, Lact. reuteri, Lact. acidophilus and Lact. plantarum) cultured in malt, barley and wheat media were investigated. The objectives were to identify the main factors influencing the growth and metabolic activity of each strain in association with the cereal substrate. METHODS AND RESULTS: All fermentations were performed without pH control. A logistic-type equation, which included a growth inhibition term, was used to describe the experimental data. In the malt medium, all strains attained high maximum cell populations (8.10-10.11 log10 cfu ml(-1), depending on the strain), probably due to the availability of maltose, sucrose, glucose, fructose (approx. 15 g l(-1) total fermentable sugars) and free amino nitrogen (approx. 80 mg l(-1)). The consumption of sugars during the exponential phase (10-12 h) resulted in the accumulation of lactic acid (1.06-1.99 g l(-1)) and acetic acid (0.29-0.59 g l(-1)), which progressively decreased the pH of the medium. Each strain demonstrated a specific preference for one or more sugars. Since small amounts of sugars were consumed by the end of the exponential phase (17-43%), the decisive growth-limiting factor was probably the pH, which at that time ranged between 3.40 and 3.77 for all of the strains. Analysis of the metabolic products confirmed the heterofermentative or homofermentative nature of the strains used, except in the case of Lact. acidophilus which demonstrated a shift towards the heterofermentative pathway. All strains produced acetic acid during the exponential phase, which could be attributed to the presence of oxygen. Lactobacillus plantarum, Lact. reuteri and Lact. fermentum continued to consume the remaining sugars and accumulate metabolic products in the medium, probably due to energy requirements for cell viability, while Lact. acidophilus entered directly into the decline phase. In the barley and wheat media all strains, especially Lact. acidophilus and Lact. reuteri, attained lower maximum cell populations (7.20-9.43 log10 cfu ml(-1)) than in the malt medium. This could be attributed to the low sugar content (3-4 g l(-1) total fermentable sugar for each medium) and the low free amino nitrogen concentration (15.3-26.6 mg l(-1)). In all fermentations, the microbial growth ceased at pH values (3.73-4.88, depending on the strain) lower than those observed for malt fermentations, which suggests that substrate deficiency in sugars and free amino nitrogen contributed to growth limitation. CONCLUSIONS: The malt medium supported the growth of all strains more than barley and wheat media due to its chemical composition, while Lact. plantarum and Lact. fermentum appeared to be less fastidious and more resistant to acidic conditions than Lact. acidophilus and Lact. reuteri. SIGNIFICANCE AND IMPACT OF THE STUDY: Cereals are suitable substrates for the growth of potentially probiotic lactic acid bacteria.

Culture Media↗

16S ribosomal DNA analysis of the faecal lactobacilli composition of human subjects consuming a probiotic strain Lactobacillus acidophilus NCFM.

AIMS: The aims of this study were to evaluate the ability of exogenous Lactobacillus acidophilus strain NCFM to survive through the human gastro-intestinal (GI) tract, and to evaluate the selectivity of Rogosa SL medium for faecal lactobacilli. METHODS AND RESULTS: The composition of the faecal lactobacilli of 10 healthy subjects was monitored for two weeks prior to, two weeks during and two weeks after the administration of the Lact. acidophilus strain NCFM consumed with skim milk (daily dose 10(10) viable cells). Fresh faecal samples were collected, processed and cultured on Rogosa SL selective medium for lactobacilli enumeration. Colonies demonstrating various morphologies were identified and purified for 16S ribosomal DNA sequence analysis for speciation of colonial genotype. The species composition of cultivable faecal lactobacilli changed considerably during consumption of the strain NCFM. CONCLUSIONS: The probiotic Lact. acidophilus strain NCFM can survive through the human GI tract, but cannot colonize itself during the two-week consumption. Rogosa SL medium is selective for faecal lactobacilli. However, genetic analysis is required for colony speciation. SIGNIFICANCE AND IMPACT OF THE STUDY: It is demonstrated that continuous consumption is necessary to maintain a high population of the probiotic strain, and that the Rogosa SL medium is reliable.

Adult↗

Lactobacillus gasseri OLL2716 as a probiotic in clarithromycin-resistant Helicobacter pylori infection.

BACKGROUNDS AND AIM: Clarithromycin (CAM)-resistant Helicobacter pylori sometimes offers serious problems with eradication by antibiotics. The aim of this study was to determine whether a probiotic can be an alternative therapy in CAM-resistant Hp infection. METHODS: The effects of Lactobacillus gasseri (strain OLL2716) on the growth of CAM-susceptible and CAM-resistant H. pylori and interleukin (IL)-8 production provoked by these strains were examined by in vitro experiments. Moreover, mice were infected with these CAM-susceptible or CAM-resistant H. pylori, and were treated with CAM or L. gasseri. RESULTS: In vitro experiments demonstrated that L. gasseri inhibited the growth of H. pylori and suppressed H. pylori-associated IL-8 production. Such effects were noted in CAM-resistant and CAM-susceptible H. pylori. Similarly, in an in vivo model of H. pylori infection, H. pylori colonization was significantly decreased by L. gasseri. CONCLUSION: Therefore, L. gasseri was found to act as a probiotic in CAM-resistant H. pylori infection.

Animals↗

The probiotic potential against vibriosis of the indigenous microflora of rainbow trout.

The antibacterial properties of the indigenous microflora of rainbow trout (Oncorhynchus mykiss Walbaum) and the potential use of inhibitory bacteria as fish probiotics were investigated. A total of 1018 bacteria and yeasts were isolated on tryptone soy agar (TSA) from skin, gills and intestine. Forty-five of these inhibited growth of the fish pathogenic bacterium Vibrio anguillarum in a well diffusion assay. The antagonism was most prominent among Pseudomonas spp., as 28 (66%) of the antagonistic bacteria belonged to this genus, despite constituting only 15% of the total tested flora. As pseudomonads are typically siderophore producers, chrome azurol S (CAS) agar was used as a semi-selective medium for isolation of antagonistic bacteria. On this medium, 75% of the iron-chelating strains were inhibitory to V. anguillarum. Eight strains out of a subset of 11 antagonists caused a 3-6 log unit reduction in the density of V. anguillarum [measured by polymerase chain reaction (PCR) detection in a most probable number (MPN) regimen] in a broth co-culture assay. Survival of rainbow trout infected with vibriosis was improved 13-43% by six out of nine antagonistic strains tested in vivo. All disease-protecting strains were pseudomonads, isolated from CAS plates, whereas two Carnobacterium spp. that were antagonistic in in vitro well diffusion assays did not alter the accumulated mortality of rainbow trout. The addition of live bacterial cultures to fish-rearing water may thus improve survival of the fish; however, in vitro antagonism could not completely predict an in vivo effect. Further studies on the underlying mechanism of activity are required to design appropriate selection criteria for fish probiotic bacteria.

Animals↗

Reuterin production by lactobacilli isolated from pig faeces and evaluation of probiotic traits.

AIMS: To determine the production of reuterin by lactobacilli isolates from pig faeces and to evaluate their potential as probiotic bacteria. METHODS AND RESULTS: Twenty-eight of 165 lactobacilli isolates produced reuterin in the presence of glycerol. Six isolates yielding high levels of reuterin with respect to type strain Lactobacillus reuteri CECT 925T were identified as Lact. reuteri. They were able to survive at pH 3 and subsequent exposure to cholic acid or oxgall, and presented bile salt hydrolase and bacteriocin-like activities. CONCLUSIONS: Reuterin production is a frequently found trait among lactobacilli isolated from pig faeces. Selected Lact. reuteri isolates were able to survive at conditions likely to be encountered throughout the gastrointestinal tract. SIGNIFICANCE AND IMPACT OF THE STUDY: High yields of reuterin may be obtained from selected isolates of Lact. reuteri. Probiotic characteristics of isolates studied in the present work suggest their application in food and feed.

Aldehydes↗

Preliminary assays for the development of a probiotic for goats.

In order to determine probiotic properties, 137 strains of lactic acid bacteria from the feces of Creole goats were screened, only six were resistant to pH 2.0 and bile salts (0.3%). Three strains identified as Lactobacillus and two as Enterococcus showed agglutination with the treated yeast. Between them, Lactobacillus DDL17, DDL19, DDL48 and Enterococcus DDE39 demonstrated high specificity in this test because the correspondent agglutination was inhibited by one sugar, suggesting the presence of a lectin-like structure in their cell walls, which could be due to adhesion ability. Another Enterococcus strain (DDE55) showed low affinity because five sugars inhibited the agglutination of the treated yeasts. The results of hydrophobic properties showed that the strains who were able to agglutinate yeasts presented similar hydrophobic characteristics as hexadecane, xylene and toluene, but high specificity was not related to a high hydrophobicity. Only two strains (Lactobacillus DDL19 and DDL48) showed aggregation with the lowest concentration of ammonium sulfate, complementing the hydrophobicity assay. Only one strain, Lactobacillus DDL48, showed an inhibition against an enteric indicator strain (Salmonella Typhimurium and Escherichia coli O111). This inhibitory action was not affected by the addition of catalase and no inhibition was detected after neutralizing the supernatant culture fluid. These strains could be pre-selected in order to complete studies focused on designing a probiotic for use in goat feed.

Agglutination Tests↗

DNA from probiotic bacteria modulates murine and human epithelial and immune function.

BACKGROUND & AIMS: The intestinal epithelium must discriminate between pathogenic and nonpathogenic bacteria and respond accordingly. The aim of this study was to examine whether bacterial DNA can serve as the molecular basis for bacterial recognition. METHODS: HT-29 monolayers were treated with various bacterial DNA and interleukin (IL)-8 secretion measured by enzyme-linked immunosorbent assay, nuclear factor kappaB activation by electrophoretic mobility shift assay and reporter assays, and IkappaB levels by Western blotting. Cytokine secretion in response to bacterial DNA was measured in murine colonic segments and splenocytes. IL-10-deficient mice were fed DNA from VSL probiotic compound daily for 2 weeks. Colons were removed and analyzed for cytokine production and inflammation. RESULTS: HT-29 cells responded with IL-8 secretion to bacterial DNA in a differential manner. In the presence of proinflammatory stimuli, VSL3 DNA inhibited IL-8 secretion, reduced p38 mitogen-activated protein kinase activation, delayed nuclear factor kappaB activation, stabilized levels of IkappaB, and inhibited proteasome function. VSL3 DNA inhibited colonic interferon (IFN)-gamma secretion in mouse colons and also attenuated a Bacteroides vulgatus-induced IFN-gamma release from murine splenocytes. In mice, VSL3 DNA attenuated a systemic release of tumor necrosis factor alpha in response to Escherichia coli DNA injection. Treatment of IL-10-deficient mice with oral VSL3 DNA resulted in a reduction in mucosal secretion of tumor necrosis factor alpha and IFN-gamma and an improvement in histologic disease. CONCLUSIONS: DNA from probiotic bacteria can limit epithelial proinflammatory responses in vivo and in vitro. Systemic and oral administration of VSL3 DNA ameliorates inflammatory responses.

Animals↗

Recombinant probiotics for treatment and prevention of enterotoxigenic Escherichia coli diarrhea.

BACKGROUND & AIMS: We have developed a therapeutic strategy for gastrointestinal infections that is based on molecular mimicry of host receptors for bacterial toxins on the surface of harmless gut bacteria. The aim of this study was to apply this to the development of a recombinant probiotic for treatment and prevention of diarrheal disease caused by enterotoxigenic Escherichia coli strains that produce heat-labile enterotoxin. METHODS: This was achieved by expressing glycosyltransferase genes from Neisseria meningitidis or Campylobacter jejuni in a harmless Escherichia coli strain (CWG308), resulting in the production of a chimeric lipopolysaccharide capable of binding heat-labile enterotoxin with high avidity. RESULTS: The strongest heat-labile enterotoxin binding was achieved with a construct (CWG308:pLNT) that expresses a mimic of lacto-N-neotetraose, which neutralized > or = 93.8% of the heat-labile enterotoxin activity in culture lysates of diverse enterotoxigenic Escherichia coli strains of both human and porcine origin. When tested with purified heat-labile enterotoxin, it was capable of adsorbing approximately 5% of its own weight of toxin. Weaker toxin neutralization was achieved with a construct that mimicked the ganglioside GM2. Preabsorption with, or coadministration of, CWG308:pLNT also resulted in significant in vivo protection from heat-labile enterotoxin-induced fluid secretion in rabbit ligated ileal loops. CONCLUSIONS: Toxin-binding probiotics such as those described here have considerable potential for prophylaxis and treatment of enterotoxigenic Escherichia coli-induced travelers' diarrhea.

Adrenal Glands↗

Probiotics and antibodies to TNF inhibit inflammatory activity and improve nonalcoholic fatty liver disease.

Ob/ob mice, a model for nonalcoholic fatty liver disease (NAFLD), develop intestinal bacterial overgrowth and overexpress tumor necrosis factor alpha (TNF-alpha). In animal models for alcoholic fatty liver disease (AFLD), decontaminating the intestine or inhibiting TNF-alpha improves AFLD. Because AFLD and NAFLD may have a similar pathogenesis, treatment with a probiotic (to modify the intestinal flora) or anti-TNF antibodies (to inhibit TNF-alpha activity) may improve NAFLD in ob/ob mice. To evaluate this hypothesis, 48 ob/ob mice were given either a high-fat diet alone (ob/ob controls) or the same diet + VSL#3 probiotic or anti-TNF antibodies for 4 weeks. Twelve lean littermates fed a high-fat diet served as controls. Treatment with VSL#3 or anti-TNF antibodies improved liver histology, reduced hepatic total fatty acid content, and decreased serum alanine aminotransferase (ALT) levels. These benefits were associated with decreased hepatic expression of TNF-alpha messenger RNA (mRNA) in mice treated with anti-TNF antibodies but not in mice treated with VSL#3. Nevertheless, both treatments reduced activity of Jun N-terminal kinase (JNK), a TNF-regulated kinase that promotes insulin resistance, and decreased the DNA binding activity of nuclear factor kappaB (NF-kappaB), the target of IKKbeta, another TNF-regulated enzyme that causes insulin resistance. Consistent with treatment-related improvements in hepatic insulin resistance, fatty acid beta-oxidation and uncoupling protein (UCP)-2 expression decreased after treatment with VSL#3 or anti-TNF antibodies. In conclusion, these results support the concept that intestinal bacteria induce endogenous signals that play a pathogenic role in hepatic insulin resistance and NAFLD and suggest novel therapies for these common conditions.

Alanine Transaminase↗

[Influence of probiotics and fibre on the incidence of bacterial infections following major abdominal surgery - results of a prospective trial].

INTRODUCTION: Early enteral nutrition with fibre and probiotics has been effective in preventing bacterial translocation and is therefore expected to reduce the incidence of postoperative bacterial infections. PATIENTS AND METHODS: In a prospective randomized trial including 172 patients following major abdominal surgery or liver transplantation, the incidence of bacterial infections was compared in patients receiving either a) conventional parenteral or enteral nutrition, b) enteral nutrition with fibre and lactobacillus plantarum 299 or c) enteral nutrition with fibre and heat inactivated lactobacilli (placebo). Liver transplant recipients were also treated with selective bowel decontamination (SBD). Routine laboratory parameters, nutritional parameters and the cellular immune status were measured preoperatively and on postoperative days 1, 5 and 10. RESULTS: Patients were comparable regarding preoperative ASA-classification, Child-Pugh classification of cirrhosis, operative data and immunosuppression. The incidence of bacterial infections after liver, gastric oder pancreas resection was 31 % in the conventional group a) compared to 4 % in the lactobacillus-group b) and 13 % in the placebo-group c). In the analysis of 95 liver transplant recipients, 13 % group b)-patients developed infections compared to 48 % group a)-patients and 34 % group c)-patients. The difference between groups a) and b) was statistically significant in both cases. In addition, the duration of antibiotic therapy was significantly shorter in the lactobacillus-group. Cholangitis and pneumonia were the most frequent infections and enterococci the most frequently isolated bacteria. Fibre and lactobacilli were well tolerated in most cases. CONCLUSION: Fibre and probiotics could lower the incidence of bacterial infections following major abdominal surgery in comparison to conventional nutrition with or without SBD. With this new concept, costs can be reduced by shortening the duration of antibiotic therapy and sparing SBD.

Adult↗

Validation of an official control method for enumeration of authorised probiotic yeast in animal feed.

An official control method in the framework of Council Directive 70/524/EEC for probiotic yeast used as feed additives was validated in a collaborative study by twenty laboratories in 12 European Countries. A pour plate method following ISO 7954 using chloramphenicol glucose yeast extract (CGYE) and a plate count method using CHROMagar Candida were used. Precision data in terms of repeatability (r) and reproducibility (R) of the method using different feeding stuffs and three inoculation levels were determined. Yeast was present in the samples in mixtures with other probiotic feed additives at a lower, a higher concentration or not present. The enumeration of yeast on CGYE agar showed for the lower and higher concentration a RSD(r) of 2.4-4.9% and a RSD(R) of 7.7-8%, respectively and was preferred by the majority of labs. CHROMagar Candida had a RSD(r) of 1.9-2.8% and a RSD(R) of 1.9-5.9%. For routine analysis the use of the pour plate technique is recommended. CHROMagar Candida can be used for confirmation of the species Saccharomyces cerevisiae. The methods are not recommended for mineral feeds. The results from this study are intended for consideration for adoption as CEN and ISO standards.

Animal Feed↗

Probiotics and intestinal health effects: a clinical perspective.

Probiotics are viable non-pathogenic micro-organisms which, when ingested, exert a positive influence on host health or physiology. We have critically analysed the evidence for the efficacy of specific probiotic strains in human gastrointestinal diseases. The best evidence can be obtained with randomised controlled trials which avoid bias. Good evidence has been obtained with several strains in the prevention or treatment of antibiotic-associated disorders, in the treatment (and to a lesser extent prevention) of gastroenteritis and acute diarrhoea and in the alleviation of lactose intolerance. We also analysed the recent randomised controlled trials performed in patients with Clostridium difficile or Helicobacter pylori, inflammatory bowel disease, irritable bowel syndrome, non-ulcer dyspepsia and colon cancer.

Anti-Bacterial Agents↗

Should yoghurt cultures be considered probiotic?

Probiotics are live micro-organisms that when administered in adequate amounts confer a health benefit on the host. Consumption of yoghurt has been shown to induce measurable health benefits linked to the presence of live bacteria. A number of human studies have clearly demonstrated that yoghurt containing viable bacteria (Streptococcus thermophilus and Lactobacillus delbrueckii sp. bulgaricus) improves lactose digestion and eliminates symptoms of lactose intolerance. Thus, these cultures clearly fulfil the current concept of probiotics.

Dietary Supplements↗

Improvement of the human intestinal flora by ingestion of the probiotic strain Lactobacillus johnsonii La1.

To exert beneficial effects for the host, for example, improving the intestinal microflora, a probiotic must reach the intestine as a viable strain. These properties must be demonstrated by in vitro as well as in vivo methods. However, only a few well-designed human clinical studies have shown these properties. Lactobacillus johnsonii La1 has been shown to give many beneficial effects for the host, but it is unclear whether a viable strain of L. johnsonii La1 has the effect of improving host intestinal microflora. In the present study, a randomised double-blind placebo-controlled cross-over trial was conducted to elucidate the effect of L. johnsonii La1 on human intestinal microflora. Twenty-two young healthy Japanese women were randomly divided into two groups, and either received fermented milk with L. johnsonii La1 or a fermented milk without L. johnsonii La1 (placebo) daily for 21 d. Consumption of the fermented milk: (a) increased total Bifidobacterium and Lactobacillus, and decreased lecithinase-positive Clostridium in the faeces; (b) increased the faecal lactic acid concentrations; (c) decreased the faecal pH; (d) increased the defecation frequency. These changes were stronger than those observed with the placebo. L. johnsonii La1 was identified in all subjects only after the consumption of the fermented milk. These results suggest that L. johnsonii La1 can contribute to improve intestinal microflora with probiotic properties.

Adult↗