Bifidobacteria In Fecal Samples Research Articles

The role of Galacto-oligosaccharides (GOS) in the recovery from dysbiosis in patients on long-term atypical antipsychotic treatment

Introduction Atypical antipsychotic (AAP) drugs are the gold-standard treatment for psychotic patients but are nowadays also widely prescribed among people with other mental disorders. Notwithstanding the benefits of AAP in terms of symptom improvement, there are severe adverse effects including the metabolic syndrome. A novel hypothesis is that part of these undesirable effects of antipsychotics could be mediated by their deleterious effects on the microbiome. This may result in dysbiosis, the disruption of bacterial species of the gut microbiota. Recently, dysbiosis has been linked to poor quality of life, depression and anxiety through the gut-brain axis. Mounting evidence proposes that prebiotic consumption may be helpful in the recovery of dysbiosis, although this effect is unclear among long-term antipsychotic users.ObjectivesThe main objective of this study is to assess the potential beneficial effects of the prebiotic Galacto-oligosaccharides (GOS) in combination with 2′-fucosyllactose (2’-FL) on the gut microbiota, by showing a relative increase in Bifidobacteria in fecal samples following intervention. The secondary objective is to assess the effects of GOS on mental wellbeing, sleep, and metabolic parameters. We hypothesize that GOS+2’FL supplementation will improve gut health, mental wellbeing, sleep, and metabolic parameters. Data will be collected 4 weeks prior to the start of the intervention during an observation only phase [t0], at baseline [t1], and after 2 [t2] and 6 [t3] weeks of GOS+2’FL intake. A follow-up will take place at week 10, 4 weeks after the intervention [t4]. Other outcomes that are assessed include the FiberScreen tool, the form of human faeces (Bristol Stool Chart), side effects and the defined daily dosis (DDD) of antipsychotic medication.MethodsThe study is a single-arm pilot study (non-randomized and non-blinded). We aim to include 30 psychiatric patients on long-term atypical antipsychotic use, irrespective of their specific psychiatric disorder, with a BMI > 25 kg/m2. Following a run-in period of 4 weeks (no intervention but all other aspects of the study), the participants will consume GOSplus (7.0 g BiotisTMGOS + 0.7 g 2’-FL) daily during the first consumption moment of the day (preferably in the morning) for 42 days. The GOSplus powder has a slightly sweet flavour. The primary endpoint is the change in Bifidobacteria in fecal samples from week 0 to week 6.ResultsThe study started recruiting participants in October 2023.ConclusionsConclusions are expected by the end of 2024.Disclosure of InterestNone Declared

Dosage-Related Prebiotic Effects of Inulin in Formula-Fed Infants.

PurposeThe aim of this study was to identify the minimally meaningful dosage of inulin leading to a prebiotic effect in Indonesian infants.MethodsIn a randomized controlled double-blinded, parallel, 3-arm intervention study, 164 healthy formula-fed infants aged 3 to 5 months first obtained formula-A (without inulin) during a 4-week adaptation period. Subsequently, 142 subjects were subjected to a 4-week feeding period by administering either formula-A (no inulin), formula-B (0.2 g/100 mL inulin) or formula-C (0.4 g/100 mL inulin). The primary outcome parameter was %-bifidobacteria in faecal samples determined using quantitative polymerase chain reaction analyses. Secondary outcome parameters were faecal %-lactobacilli, pH and stool frequency, and consistency. Growth and tolerance/adverse effects were recorded as safety parameters.ResultsTypical %-bifidobacteria and %-lactobacilli at the end of the adaptation period in the study population were 14% and 2%, respectively. For faecal pH, significant differences between formula groups A vs. C and A vs. B were found at the end of the intervention period. Testing for differences in faecal %-bifidobacteria and %-lactobacilli between groups was hampered by non-normal data set distributions; no statistically significant differences were obtained. Comparisons within groups revealed that only in formula group C, all the three relevant parameters exhibited a significant effect with an increase in faecal %-bifidobacteria and %-lactobacilli and a decrease in pH.ConclusionA consistent prebiotic effect along with a decrease in pH and increase in %-bifidobacteria and %-lactobacilli was found only in the group administered 0.4 g inulin/100 mL.

Novel encapsulation improves recovery of probiotic strains in fecal samples of human volunteers

Probiotic supplements can contribute to maintaining health and ameliorating various disease symptoms. Probiotics can be delivered in many forms with crucial differences in their survival during gastrointestinal (GI) passage. Previously, a novel encapsulation, Probiotic Pearls™ Acidophilus, Integrative Therapeutics, LLC, USA (Pearls), was shown to increase survival in vitro after exposure to gastric conditions. Here, we compare fecal recovery in human volunteers consuming Pearls or a conventional hard-shelled gelatin capsule. We performed a randomized double-blinded, two-armed trial, with six healthy subjects in each 12-day study arm. In fecal samples collected at baseline, twice during the intervention period, and after washout, we compared colony counts between the two encapsulation methods. The identity of the colonies was confirmed by colony morphology, strain-specific PCR, and 16S rRNA gene sequencing. We further performed a comprehensive 16S rRNA gene sequencing-based analysis to identify differential effects on overall microbiota composition. We detected an average log increase in bifidobacteria of 0.152cfu/g with gelatin and 0.651cfu/g with Pearls capsules (p>0.05). Total lactobacilli counts increased in both groups with no difference between the groups. However, the supplemented Lactobacillus acidophilus NCFM decreased to baseline levels within 7days after end of supplementation with gelatin capsules while 3.11 log cfu/g higher counts compared to baseline (p=0.05) remained for Pearls. Targeted qPCR largely confirmed the trends observed by viable plate counts. Protecting the probiotic strains by Pearls encapsulation results in higher recovery rates of the supplemented lactobacilli and bifidobacteria in fecal samples and increased persistence, suggesting an improved survival and viability that might increase efficacy towards achieving desired health benefits.

Bifidobacteria strains isolated from stools of iron deficient infants can efficiently sequester iron.

BackgroundBifidobacteria is one of the major gut commensal groups found in infants. Their colonization is commonly associated with beneficial effects to the host through mechanisms like niche occupation and nutrient competition against pathogenic bacteria. Iron is an essential element necessary for most microorganisms, including bifidobacteria and efficient competition for this micronutrient is linked to proliferation and persistence. For this research we hypothesized that bifidobacteria in the gut of iron deficient infants can efficiently sequester iron. The aim of the present study was to isolate bifidobacteria in fecal samples of iron deficient Kenyan infants and to characterize siderophore production and iron internalization capacity.ResultsFifty-six bifidobacterial strains were isolated by streaking twenty-eight stool samples from Kenyan infants, in enrichment media. To target strains with high iron sequestration mechanisms, a strong iron chelator 2,2-dipyridyl was supplemented to the agar media. Bifidobacterial isolates were first identified to species level by 16S rRNA sequencing, yielding B. bifidum (19 isolates), B. longum (15), B. breve (11), B. kashiwanohense (7), B. pseudolongum (3) and B. pseudocatenulatum (1). While most isolated bifidobacterial species are commonly encountered in the infantile gut, B. kashiwanohense was not frequently reported in infant feces. Thirty strains from culture collections and 56 isolates were characterized for their siderophore production, tested by the CAS assay. Siderophore activity ranged from 3 to 89% siderophore units, with 35 strains (41%) exhibiting high siderophore activity, and 31 (36%) and 20 (23%) showing intermediate or low activity. The amount of internalized iron of 60 bifidobacteria strains selected for their siderophore activity, was in a broad range from 8 to118 μM Fe. Four strains, B. pseudolongum PV8-2, B. kashiwanohense PV20-2, B. bifidum PV28-2a and B. longum PV5-1 isolated from infant stool samples were selected for both high siderophore activity and iron internalization.ConclusionsA broad diversity of bifidobacteria were isolated in infant stools using iron limited conditions, with some strains exhibiting high iron sequestration properties. The ability of bifidobacteria to efficiently utilize iron sequestration mechanism such as siderophore production and iron internalization may confer an ecological advantage and be the basis for enhanced competition against enteropathogens.Electronic supplementary materialThe online version of this article (doi:10.1186/s12866-014-0334-z) contains supplementary material, which is available to authorized users.

Monomer and Linkage Type of Galacto-Oligosaccharides Affect Their Resistance to Ileal Digestion and Prebiotic Properties in Rats1–3

A detailed study was performed to compare the in vivo ileal digestibility and modulatory effects in fecal microbiota of novel galacto-oligosaccharides (GOS) derived from lactulose [GOS-Lu; degree of polymerization (DP) ≥2, 14.0% trisaccharides] and commercial GOS derived from lactose (GOS-La; DP ≥3, 35.1% trisaccharides) in growing rats (5 wk old). Rats were fed either a control diet or diets containing 1% (wt:wt) of GOS-Lu or GOS-La for 14 d. Quantitative analysis of carbohydrates from dietary and ileal samples demonstrated that the trisaccharide fraction of GOS-Lu was significantly more resistant to gut digestion than that from GOS-La, as indicated by their ileal digestibility rates of 12.5 ± 2.6% and 52.9 ± 2.7%, respectively, whereas the disaccharide fraction of GOS-Lu was fully resistant to the extreme environment of the upper digestive tract. The low ileal digestibility of GOS-Lu was due to the great resistance of galactosyl-fructoses to mammalian digestive enzymes, highlighting the key role played by the monomer type and linkage involved in the oligosaccharide chain. The partial digestion of GOS-La trisaccharides showed that glycosidic linkages (1→6) and (1→2) between galactose and glucose monomers were significantly more resistant to in vivo gastrointestinal digestion than the linkage (1→4) between galactose units. The absence of GOS-La and GOS-Lu digestion-resistant oligosaccharides in fecal samples indicated that they were readily fermented within the large intestine, enabling both types of GOS to have a potential prebiotic function. Indeed, compared with controls, the GOS-Lu group had significantly more bifidobacteria in fecal samples after 14 d of treatment. The number of Eubacterium rectale also was greater in the GOS-Lu and GOS-La groups than in controls. These novel data support a direct relationship between patterns of resistance to digestion and prebiotic properties of GOS.

The presence of bifidobacteria in social insects, fish and reptiles

The occurrence and species distribution of bifidobacteria in the digestive tract of important representatives of social insects such as ants, bees, wasps and bumblebees as well as the incidence of bifidobacteria in fecal samples of several species of vertebrates represented mainly by reptiles was assigned by culture-independent method based on DGGE and real time PCR. Bifidobacteria were present in the gut of most social insects--honey bees, wasps, cockroaches and bumblebees, except for ants. In honey bees, where the counts of bifidobacteria ranged from 2 to 8% of the total bacteria, the most common species seemed to be Bifidobacterium indicum. Proportion of bifidobacteria was found in broad range from 0.1 to 35-37% in wasps and cockroaches; the variance of bifidobacteria in bumblebees was lower, ranging from 1 to 7% of total bacterial count. Among studied vertebrates, the detectable presence of bifidobacteria was found only in trout (1.1%) and geckos (0.2%), but large amount of these bacteria was observed in Vietnamese box turtle, where bifidobacteria represented nearly one-fourth (22%) of total bacterial counts.

Growth of infant faecal bifidobacteria and clostridia on prebiotic oligosaccharides in in vitro conditions

Our aim was to isolate bifidobacteria and clostridia from infant faeces and to test the growth of bifidobacteria and clostridia on prebiotic oligosaccharides. Seventy breast-fed infants aged between 3 and 253 days were tested for the presence of bifidobacteria and clostridia in their faeces. Ten strains of clostridia and 10 strains of bifidobacteria were isolated from infant faecal samples. Four strains of bifidobacteria originated from culture collections and 1 strain from fermented milk product were also tested. Subsequently, bacterial isolates were tested for their growth on prebiotic oligosaccharides in, in vitro conditions. Forty-six infants exhibited high numbers of bifidobacteria (usually higher than 9 log CFU/g) in their faeces. There were undetectable amounts of bifidobacteria in faecal samples in 24 of the studied infants (34%), these babies on the other hand possessed significant amounts of clostridia in their faecal flora. Both bifidobacteria and clostridia utilized all substrates tested. Bifidobacteria grew significantly better in the medium with galactooligosaccharides. Higher growth of clostridia was observed on raffinose and lactulose. Conversely, bifidobacteria grew slightly better in the medium with stachyose, inulin, Raftilose ® P85 and P95. However, these differences were not significant. Our results suggest that commercially available prebiotics support the growth of infant faecal clostridia. It is therefore questionable if bifidobacteria-deficient infants should be supplemented with prebiotics.

Bifidogenic Effects of Solid Weaning Foods With Added Prebiotic Oligosaccharides

Breast-fed infants have relatively high proportions of faecal bifidobacteria. This bifidogenic microbiota is at least partly explained by the high levels of prebiotic oligosaccharides in human milk. The present study aimed at testing the effect of solid foods with added prebiotic galacto- and fructo-oligosaccharides (GOS/FOS) on the composition of the intestinal microbiota of fully formula-fed infants during the weaning period. The study was a double-blind, randomised trial with an intervention period of 6 weeks. Infants aged 4 to 6 months who were about to start consuming solid foods were randomised to receive either weaning products with a mixture of GOS/FOS or control weaning products with maltodextrin. After an adjustment period, the presented daily dose of GOS/FOS was 4.5 g. Total numbers of bacteria and bifidobacteria in faecal samples were analysed with fluorescent in situ hybridization. Thirty-five infants were included in the study, and 20 infants were included in a per-protocol analysis. In the GOS/FOS group, the faecal percentage of bifidobacteria significantly increased from 43% to 57% (P = 0.031) from week 0 to week 6, but did not significantly change in the control group (36% and 32%, respectively; P = 0.387). The change in the percentage of bifidobacteria between week 0 and week 6 in the GOS/FOS was significantly different from this change in the control group (P = 0.026). We conclude that addition of GOS/FOS to solid foods induces an increase in the faecal proportion of bifidobacteria in the intestinal microbiota of fully formula-fed infants with an established, mixed-type microbiota in the weaning period.

Identification, detection, and enumeration of human bifidobacterium species by PCR targeting the transaldolase gene.

Methods that enabled the identification, detection, and enumeration of Bifidobacterium species by PCR targeting the transaldolase gene were tested. Bifidobacterial species isolated from the feces of human adults and babies were identified by PCR amplification of a 301-bp transaldolase gene sequence and comparison of the relative migrations of the DNA fragments in denaturing gradient gel electrophoresis (DGGE). Two subtypes of Bifidobacterium longum, five subtypes of Bifidobacterium adolescentis, and two subtypes of Bifidobacterium pseudocatenulatum could be differentiated using PCR-DGGE. Bifidobacterium angulatum and B. catenulatum type cultures could not be differentiated from each other. Bifidobacterial species were also detected directly in fecal samples by this combination of PCR and DGGE. The number of species detected was less than that detected by PCR using species-specific primers targeting 16S ribosomal DNA (rDNA). Real-time quantitative PCR targeting a 110-bp transaldolase gene sequence was used to enumerate bifidobacteria in fecal samples. Real-time quantitative PCR measurements of bifidobacteria in fecal samples from adults correlated well with results obtained by culture when either a 16S rDNA sequence or the transaldolase gene sequence was targeted. In the case of samples from infants, 16S rDNA-targeted PCR was superior to PCR targeting the transaldolase gene for the quantification of bifidobacterial populations.

Effects of Culture-Powder of Propionibacterium freudenreichii ET-3 on Fecal Microflora of Normal Adults

The effect of a culture powder of Propionibacterium freudenreichii ET-3 cells containing a bifidogenic growth stimulator (BGS) on fecal flora was studied in twelve healthy subjects with a mean age of 42.6 (range, 27-56 years). One gram of BGS powder containing 17.4 U of BGS activity was administered for 14 days, three times a day after meals. A significantly higher number of bifidobacteria in fecal samples was observed during the intake period of the BGS powder. The frequency of occurrence of the bifidobacteria also increased from 92% to 100%. These results indicate that the BGS acts in the intestine as a growth stimulator of bifidobacteria when the BGS powder is administered.

Digoxigenin-Labeled Deoxyribonucleic Acid Probes for the Enumeration of Bifidobacteria in Fecal Samples

The numbers of bifidobacteria in fecal samples were specifically determined by colony hybridization with the mixture of digoxigenin-labeled DNA probes that were prepared from whole chromosomal DNA of Bifidobacterium longum 6001 and Bifidobacterium adolescentis 6003. These DNA probes strongly hybridized with DNA of B. longum, B. adolescentis, Bifidobacterium breve, Bifidobacterium suis, Bifidobacterium infantis, Bifidobacterium bifidum, Bifidobacterium angulatum, and Bifidobacterium animalis. Detectable positive signals with DNA of Bifidobacterium pseudolongum ssp. pseudolongum, Bifidobacterium catenulatum, and Bifidobacterium thermophilum were also found after hybridization. When dotblot hybridization was performed with whole cells of 47 reference strains containing 11 species (16 strains) of bifidobacteria, all of the bifidobacteria tested could be specifically detected by using these DNA probes; Lactobacillus fermentum JCM 1173, however, showed a slight nonspecific signal. The counts of bifidobacteria by colony hybridization in the fecal samples of four of the five subjects were the same as the counts that were obtained by the conventional method using BL agar medium. Furthermore, no significant difference existed in the number of bifidobacteria that were determined by either method.