Beneficial effects of Bifidobacterium longum subsp. longum BB536 on human health: Modulation of gut microbiome as the principal action

Effects of 2'-fucosyllactose on the viability of starter cultures and Bifidobacterium strains of human origin in yogurt during refrigerated storage

2'-Fucosyllactose (2'-FL) is postulated to provide health benefits and promote the growth of probiotics. This work was undertaken to study the effects of 2'-FL on the viability of starter cultures and Bifidobacterium strains of human origin in yogurt during refrigerated storage. Yogurts were produced containing 2'-FL (0 or 2 g/L) and Bifidobacterium strains of human origin (Bifidobacterium longum subsp. longum BB536 or Bifidobacterium longum subsp. infantis ATCC 15697) at a concentration of at least 109 CFU/mL. All yogurts were stored at 4°C for 5 weeks. Results showed that 2'-FL was stable in yogurts for at least 5 weeks of cold storage, and the addition of 2'-FL did not significantly alter yogurt fermentation parameters, associated metabolites, and the viability of mixed yogurt starter cultures and Bifidobacterium strains (p > 0.05). The addition of bifidobacteria had a negative impact (p < 0.05) on the survival rate of starter cultures, Streptococcus thermophilus and Lactobacillus delbureckii subsp. bulgaricus. Meanwhile, it is difficult to maintain a high survival rate of bifidobacteria in final yogurt products, and the addition of 2'-FL could not enhance the viability of bifidobacteria. B. longum BB536 survived at a level higher than 106 CFU/g for 28 days, while B. infantis ATCC15697 maintained this level for only 7 days. In summary, this study has shown the impact of 2'-FL and bifidobacterial species on yogurt properties, and results suggest that it is promising to use 2'-FL in yogurt products as a prebiotic. PRACTICAL APPLICATION: Yogurt is known for its beneficial effects on human health and nutrition. This study reported the production of symbiotic yogurt containing bifidobacteria and 2'-fucosyllactose (2'-FL) as a functional food for specified health uses. The viability of yogurt starter cultures and probiotic bifidobacterial strains was analyzed in this study. Moreover, this research demonstrated that 2'-FL could be added to yogurt without affecting the characteristics of yogurt significantly.

Investigation of Effects of Novel Bifidobacterium longum ssp. longum on Gastrointestinal Microbiota and Blood Serum Parameters in a Conventional Mouse Model

Representatives of the genus Bifidobacterium are widely used as probiotics to modulate the gut microbiome and alleviate various health conditions. The action mechanisms of probiotics rely on their direct effect on the gut microbiota and the local and systemic effect of its metabolites. The main purpose of this animal experiment was to assess the biosafety of the Bifidobacterium longum strain BIOCC1719. Additional aims were to characterise the influence of the strain on the intestinal microbiota and the effect on several health parameters of the host during 15- and 30-day oral administration of the strain to mice. The strain altered the gut microbial community, thereby altering luminal short-chain fatty acid metabolism, resulting in a shift in the proportions of acetic, butyric, and propionic acids in the faeces and serum of the test group mice. Targeted metabolic profiling of serum revealed the possible ability of the strain to positively affect the hosts' amino acids and bile acids metabolism, as the cholic acid, deoxycholic acid, aspartate, and glutamate concentration were significantly higher in the test group. The tendency to increase anti-inflammatory polyamines (spermidine, putrescine) and neuroprotective 3-indolepropionic acid metabolism and to lower uremic toxins (P-cresol-SO4, indoxyl-SO4) was registered. Thus, B. longum BIOCC1719 may exert health-promoting effects on the host through modulation of the gut microbiome and the host metabolome via inducing the production of health-promoting bioactive compounds. The health effects of the strain need to be confirmed in clinical trials with human volunteers.

Garfield R, Yang J. Characteristics of cervicovaginal microflora at different cervical maturity during late pregnancy: A nested case-control study

OBJECTIVE

The mechanism of cervical ripening in late pregnancy is still unclear. The vaginal microbiome has been reported to correlate with the preterm birth and short cervix in pregnant women. However, the associations between the cervical maturity and the vaginal microbiome are still poorly understood. We aim to analyze the cervicovaginal microflora in women with ripe cervix and in those who are unripe when delivering at term.

METHODS

Cervicovaginal swabs were collected between 40 and 41 weeks of gestation from the following 2 different groups of patients: ripe group (n = 25) and unripe group (n = 25). Samples were tested using 16S ribosomal RNA gene high-throughput sequencing and analyzed by bioinformatics platform.

RESULTS

This study highlights the relationship between cervical maturity during late pregnancy and the composition of the cervicovaginal microflora. Both α- and β-diversity analyses demonstrated significant differences between women with a ripe cervix and those with an unripe cervix. Notably, the Lactobacillus profile was found to be closely linked to cervical maturity. There was a significant difference in the vaginal community state type, with CST IV being more prevalent in women with an unripe cervix. Furthermore, the association between CST IV and the unripe cervix group, as indicated by the odds ratio of 8.6, underscores its relevance in evaluating cervical maturity, when compared to other Lactobacillus-dominant community state types. Additionally, several bacterial taxa, particularly Lactobacillus, exhibited differential relative abundances between the two groups.

CONCLUSION

This study provided significant evidence regarding the relationship between the vaginal microbiome and cervical maturity, highlighting the differential diversity, community state types, and specific bacterial taxa, such as Lactobacillus, that are associated with cervical maturation status. These findings contributed to our understanding of the dynamics of the cervicovaginal microflora during late pregnancy and its implications for cervical health.

A bacterial sensor taxonomy across earth ecosystems for machine learning applications

Microbial communities have evolved to colonize all ecosystems of the planet, from the deep sea to the human gut. Microbes survive by sensing, responding, and adapting to immediate environmental cues. This process is driven by signal transduction proteins such as histidine kinases, which use their sensing domains to bind or otherwise detect environmental cues and "transduce" signals to adjust internal processes. We hypothesized that an ecosystem's unique stimuli leave a sensor "fingerprint," able to identify and shed insight on ecosystem conditions. To test this, we collected 20,712 publicly available metagenomes from Host-associated, Environmental, and Engineered ecosystems across the globe. We extracted and clustered the collection's nearly 18M unique sensory domains into 113,712 similar groupings with MMseqs2. We built gradient-boosted decision tree machine learning models and found we could classify the ecosystem type (accuracy: 87%) and predict the levels of different physical parameters (R2 score: 83%) using the sensor cluster abundance as features. Feature importance enables identification of the most predictive sensors to differentiate between ecosystems which can lead to mechanistic interpretations if the sensor domains are well annotated. To demonstrate this, a machine learning model was trained to predict patient's disease state and used to identify domains related to oxygen sensing present in a healthy gut but missing in patients with abnormal conditions. Moreover, since 98.7% of identified sensor domains are uncharacterized, importance ranking can be used to prioritize sensors to determine what ecosystem function they may be sensing. Furthermore, these new predictive sensors can function as targets for novel sensor engineering with applications in biotechnology, ecosystem maintenance, and medicine.IMPORTANCEMicrobes infect, colonize, and proliferate due to their ability to sense and respond quickly to their surroundings. In this research, we extract the sensory proteins from a diverse range of environmental, engineered, and host-associated metagenomes. We trained machine learning classifiers using sensors as features such that it is possible to predict the ecosystem for a metagenome from its sensor profile. We use the optimized model's feature importance to identify the most impactful and predictive sensors in different environments. We next use the sensor profile from human gut metagenomes to classify their disease states and explore which sensors can explain differences between diseases. The sensors most predictive of environmental labels here, most of which correspond to uncharacterized proteins, are a useful starting point for the discovery of important environment signals and the development of possible diagnostic interventions.

A Novel Bifidobacterium longum ssp. longum Strain with Pleiotropic Effects

Postbiotics are gaining increasing interest among the scientific community as well as at the level of food processing enterprises. The aim of this preliminary study was to characterise the metabolic diversity of a novel Bifidobacterium longum strain, BIOCC 1719, of human origin. The change after 24 h cultivation in three media was assessed using a metabolomic approach. Milk-based substrates favoured the activity of the strain, promoting the production of B vitamins, essential amino acids, bile acids, and fatty acids. Vitamins B1, B2, B6, B7, and B12 (with an average increase of 20-30%) were produced in both whole milk and whey; the increased production in the latter was as high as 100% for B7 and 744% for B12. The essential amino acids methionine and threonine were produced (>38%) in both milk and whey, and there was an increased production of leucine (>50%) in milk and lysine (126%) in whey. Increases in the content of docosahexaenoic acid (DHA) by 20%, deoxycholic acid in milk and whey (141% and 122%, respectively), and cholic acid (52%) in milk were recorded. During the preliminary characterisation of the metabolic diversity of the novel B. longum strain, BIOCC 1719, we identified the bioactive compounds produced by the strain during fermentation. This suggests its potential use as a postbiotic ingredient to enrich the human diet.

Effects of a Nutraceutical Multicompound, with Probiotics, Hericium, PEA, and Undaria in Patients with Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a functional gastrointestinal condition. Probiotics and other nutraceutical compounds can have specific indications in the context of IBS. A retrospective analysis was conducted on 123 IBS patients in order to evaluate the effects of an oral probiotic-based dietary supplement (Colicron, one cps/day for 4 wk) on stool consistency and pain intensity. Different time points were defined as follows: baseline (T0), 2 wk of treatment (T2), and 4 wk of treatment (T4). Stool consistency was assessed by using the Bristol Stool Scale. Pain intensity was evaluated by the Visual Analogue Scale (VAS). Patients who were initially categorized as normal retained regular bowel movements throughout the study. Both patients with constipation and diarrhea showed an improvement in the Bristol Stool Scale. The score increased from 1.5 ± 0.5 to 3.3 ± 0.7 (p < 0.001) and decreased from 6.5 ± 0.7 to 4.3 ± 0.9 (p < 0.001) at T4, respectively, compared to T0. The VAS score for pain in the pooled IBS patients improved from 6.7 ± 2.2 to 2.8 ± 1.9 at T0 vs T4 (p < 0.001), with a similar trend also observed when patients were categorized based on stool consistency: normal (from 5.2 ± 1.9 to 2.9 ± 1.7), constipation (from 7.5 ± 1.3 to 3.2 ± 2.2), and diarrhea (6.7 ± 2.3 to 2.5 ± 1.9) (p < 0.001).Colicron could be useful in symptom relief, reducing abdominal pain and improving stool consistency of IBS patients. However, further controlled clinical trials are needed to confirm these preliminary findings.

The Potential Immunomodulatory Effect of Bifidobacterium longum subsp. longum BB536 on Healthy Adults through Plasmacytoid Dendritic Cell Activation in the Peripheral Blood

The interaction between the gut microbiota and the host can influence the host's immune system. Bifidobacterium, a commensal genus of gut bacteria, seems to have positive effects on host health. Our previous clinical research showed that B. longum subsp. longum BB536 enhanced innate and adaptive immune responses in elderly individuals with a lower grade of immunity, but the immunomodulatory mechanism is still unclear. In this study, dendritic cell (DC) surface markers in peripheral blood mononuclear cells isolated from healthy individuals were evaluated through coculture with heat-killed BB536. DC markers, innate immune activity and cytokine levels in plasma were also evaluated by a randomized, double-blind, placebo-controlled, parallel-group study (UMIN000045564) with 4 weeks of continuous live BB536 intake. BB536 significantly increased the expression of CD86 and HLA-DR on plasmacytoid DCs (pDCs) in vitro. Compared to placebo (n = 48), a significant increase in the expression of CD86 on peripheral pDCs was detected at week 4 of live BB536 intake (n = 49; 1 × 1010 CFU/day). Furthermore, coculture with hk-BB536 significantly increased the IFNγ expression level and demonstrated trends of increased IFNα1 and IFNβ expression. These findings suggest that consumption of BB536 has potential immunomodulatory effects on healthy individuals through the activation of peripheral pDCs.

Upper respiratory tract microbiome profiles in SARS-CoV-2 Delta and Omicron infected patients exhibit variant specific patterns and robust prediction of disease groups

IMPORTANCE

The role of the upper respiratory tract (URT) microbiome in predicting lung health has been documented in several studies. The dysbiosis in COVID patients has been associated with disease outcomes by modulating the host immune system. However, although it has been known that different SARS-CoV-2 variants manifest distinct transmissibility and mortality rates in human populations, their effect on the composition and diversity of the URT microbiome has not been studied to date. Unlike the older variant (Delta), the newer variant (Omicron) have become more transmissible with lesser mortality and the symptoms have also changed significantly. Hence, in the present study, we have investigated the change in the URT microbiome associated with Delta and Omicron variants and identified variant-specific signatures that will be useful in the assessment of lung health and can be utilized for nasal probiotic therapy in the future.

Mechanistic insights into the role of probiotics in modulating immune cells in ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is a persistent inflammatory disorder that affects the gastrointestinal tract, mainly the colon, which is defined by inflammatory responses and the formation of ulcers. Probiotics have been shown to directly impact various immune cells, including dendritic cells (DCs), macrophages, natural killer (NK) cells, and T and B cells. By interacting with cell surface receptors, they regulate immune cell activity, produce metabolites that influence immune responses, and control the release of cytokines and chemokines.

METHODS

This article is a comprehensive review wherein we conducted an exhaustive search across published literature, utilizing reputable databases like PubMed and Web of Science. Our focus centered on pertinent keywords, such as "UC," 'DSS," "TNBS," "immune cells," and "inflammatory cytokines," to compile the most current insights regarding the therapeutic potential of probiotics in managing UC.

RESULTS

This overview aims to provide readers with a comprehensive understanding of the effects of probiotics on immune cells in relation to UC. Probiotics have a crucial role in promoting the proliferation of regulatory T cells (Tregs), which are necessary for preserving immunological homeostasis and regulating inflammatory responses. They also decrease the activation of pro-inflammatory cells like T helper 1 (Th1) and Th17 cells, contributing to UC development. Thus, probiotics significantly impact both direct and indirect pathways of immune cell regulation in UC, promoting Treg differentiation, inhibiting pro-inflammatory cell activation, and regulating cytokine and chemokine release.

CONCLUSION

Probiotics demonstrate significant potential in modulating the immune reactions in UC. Their capacity to modulate different immune cells and inflammation-related processes makes them a promising therapeutic approach for managing UC. However, further studies are warranted to optimize their use and fully elucidate the molecular mechanisms underlying their beneficial effects in UC treatment.

The impact of antimicrobial food additives and sweeteners on the growth and metabolite production of gut bacteria

Metabolic disorders caused by the imbalance of gut microbiota have been associated with the consumption of processed foods. Thus, this study aimed to evaluate the effects of antimicrobial food additives (benzoate, sorbate, nitrite, and bisulfite) and sweeteners (saccharin, stevia, sucralose, aspartame, and cyclamate) on the growth and metabolism of some gut and potentially probiotic bacterial species. The effects on the growth of Bifidobacterium longum, Enterococcus faecium, Lactobacillus acidophilus, and Lactococcus lactis subsp. lactis cultures were investigated using a turbidimetric test and by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). To evaluate the metabolic activity, the cultures were exposed to compounds with the highest antimicrobial activity, subjected to cultivation with inulin (1.5%), and analyzed by liquid chromatography for the production of short-chain fatty acids (acetate, propionate, and butyrate). The results showed that potassium sorbate (25 mg/mL), sodium bisulfite (0.7 mg/mL), sodium benzoate, and saccharin (5 mg/mL) presented greater antimicrobial activity against the studied species. L. lactis and L. acidophilus bacteria had reduced short-chain fatty acid production after exposure to saccharin and sorbate, and B. longum after exposure to sorbate, in comparison to controls (acetic acid reduction 1387 μg/mL and propionic 23 μg/mL p < 0.05).

Metagenomic Studies Reveal the Evidence of Akkermansia muciniphila and Other Probiotic Bacteria in the Gut of Healthy and Enterocytozoon hepatopenaei (EHP)-Infected Farmed Penaeus vannamei

Penaeus vannamei (whiteleg shrimp) is the most widely cultured shrimp globally. Enterocytozoon hepatopenaei (EHP), a microsporidian parasite, infects P. vannamei and causes severe growth retardation, subsequent production, and economic losses in the shrimp culture. The influence of EHP infection in the shrimp gut microbiota is poorly studied, and this would be an interesting area to investigate since the gut microbiome of shrimp influences a number of key host processes such as digestion and immunity. In this study, a metagenomic approach was followed to compare the overall species richness of the gut microbiota of EHP-infected and healthy P. vannamei. Bacterial genomic DNA from the healthy and EHP-infected gut sample were profiled for the bacterial 16S rRNA gene, targeting the V3-V4 conserved region. Operational taxonomic units (OTUs), an approximation of definitive taxonomic identity, were identified based on the sequence similarity within the sample reads and clustered together using a cut-off of 97% identity using UCLUST. The OTUs were then used for the computation of alpha diversity and beta diversity for each sample. EHP-infected gut sample showed lower bacterial abundance throughout the family, class, order, genus, and species levels when compared to healthy gut sample. This study shows that the shrimp gut microbiota is sensitive and exhibits a high level of plasticity during a microsporidian infection like EHP. Furthermore, Akkermansia muciniphila, a novel probiotic bacterium, has been reported in the shrimp gut for the first time.

In vitro ruminal fermentation and cow-to-mouse fecal transplantations verify the inter-relationship of microbiome and metabolome biomarkers: potential to promote health in dairy cows

Introduction

There are differences in the gut microbiome and metabolome when the host undergoes different physical or pathological conditions. However, the inter-relationship of microbiome and metabolome biomarkers to potentially promote the health of dairy cows needs to be studied. Further, the development of next-generation probiotics for dairy cattle health promotion has not been demonstrated.

Objective

In the present study, we identified the microbiome and metabolome biomarkers associated with healthy cows.

Methods

We analyzed the relationships of the ruminal microorganism profile and metabolites between healthy and mastitis lactating dairy cows. The roles of bacterial biomarker were further verified by in vitro fermentation and cow-to-mouse fecal microbiota transplantation (FMT).

Results

Two species, Ruminococcus flavefaciens and Bifidobacterium longum subsp. longum, and six rumen metabolites were positively correlated with healthy cows by Spearman's correlation analysis. Through in vitro ruminal fermentation, inoculating R. flavefaciens and B. longum subsp. longum showed the upregulation of the levels of putrescine, xanthurenic acid, and pyridoxal in the mastitis ruminal fluid, which confirmed the inter-relationships between these microbiota and metabolites associated with healthy cows. Further, we verified the role of R. flavefaciens and B. longum subsp. longum in promoting health by FMT. The administration of R. flavefaciens and B. longum subsp. longum reduced the death rate and recovered the bodyweight loss of germ-free mice caused by FMT mastitis feces.

Discussion

We provided evidence that the bacterial biomarkers alter downstream metabolites. This could indirectly indicate that the two bacterial biomarkers have the potential to be used as next-generation probiotics for dairy cattle, although it needs more evidence to support our hypothesis. Two species, R. flavefaciens and B. longum subsp. longum, with three metabolites, putrescine, xanthurenic acid, and pyridoxal, identified in the ruminal fluid, may point to a new health-promoting and disease-preventing approach for dairy cattle.

Meta-analysis reveals different functional characteristics of human gut Bifidobacteria associated with habitual diet

Dietary habits contribute to the composition and function of the gut microbiota. Different dietary structures, including vegan, vegetarian, and omnivorous diets, affect intestinal Bifidobacteria; however, the relationship between Bifidobacterial function and host metabolism in subjects with different dietary patterns is unclear. Here, we analyzed five metagenomics studies and six 16S sequencing studies, including 206 vegetarians (VG), 249 omnivores (O), and 270 vegans (V), through an unbiased theme-level meta-analysis framework and discovered that diet significantly affects the composition and functionality of intestinal Bifidobacteria. The relative abundance of Bifidobacterium pseudocatenulatum was significantly higher in V than in O and Bifidobacterium longum, Bifidobacterium adolescentis, and B. pseudocatenulatum differed significantly in carbohydrate transport and metabolism in subjects with different diet types. Diets high in fiber were associated with B. longum with increased capacity for carbohydrate catabolism and genes encoding GH29 and GH43_27 were significantly enriched in V. Bifidobacterium adolescentis and B. pseudocatenulatum, associated with O, had a higher prevalence of the genes related to carbohydrate transport and metabolism, which showed the enrichment of GH26 and GH27 families. The same Bifidobacterium species has different functions in subjects with different diet types, resulting in different physiological significance. The diversification and functionalities of Bifidobacterial species in the gut microbiome can be influenced by the host diet and this aspect should be considered when studying host-microbe associations.

Genome Analysis of Potential Probiotic Levilactobacillus brevis AcCh91 Isolated from Indian Home-Made Fermented Milk Product (Chhurpi)

Consumption of naturally fermented milk (NFM) products is the dietary culture in India. The mountainous people of Arunachal Pradesh in India prepare the assorted artisanal home-made NFM products from cow and yak milk. Previously, we isolated and identified 76 strains of lactic acid bacteria (LAB) from NFM products of Arunachal Pradesh, viz. mar, chhurpi and churkam. We hypothesized that some of these LAB strains may possess probiotic potentials; hence, we investigated the probiotic potentials of these strains. On the basis of in vitro and genetic screening for probiotic attributes including haemolytic ability, 20 LAB strains were selected out of 76 strains, for further analysis. Using in silico analysis, viz. multivariate heatmap and PCA (principal component analysis) biplot, Levilactobacillus brevis AcCh91 was selected as the most promising probiotic strain, which was further characterized by the whole-genome analysis. Lev. brevis AcCh91 showed the highest survival rate of 93.38% in low pH and 86.68 ± 2.69% in low bile and the highest hydrophobicity average of 86.34 ± 5.53%. This strain also showed auto-aggregation and co-aggregation with antimicrobial properties against the pathogens, showed ability to produce beta-galactosidase and cholesterol reduction property and, most importantly, produced GABA, an important psychobiotic element. Genomic analysis of Lev. brevis AcCh91 showed the presence of genes corresponding to GABA, vitamins, amino acids, cholesterol reduction, immunomodulation, bioactive peptides and antioxidant activity. The absence of antimicrobial-resistant genes and virulence factors was observed. Hence, genome analysis supports the probiotic potentials of Lev. brevis AcCh91, which may be further investigated to understand its health-promoting properties.

Study of the biosynthesis and functionality of polyphosphate in Bifidobacterium longum KABP042

Polyphosphate (poly-P) biosynthesis in bacteria has been linked to many physiological processes and has been characterized as an interesting functional molecule involved in intestinal homeostasis. We determined the capacity for poly-P production of 18 probiotic strains mainly belonging to Bifidobacterium and former Lactobacillus genera, showing that poly-P synthesis varied widely between strains and is dependent on the availability of phosphate and the growth phase. Bifidobacteria were especially capable of poly-P synthesis and poly-P kinase (ppk) genes were identified in their genomes together with a repertoire of genes involved in phosphate transport and metabolism. In Bifidobacterium longum KABP042, the strain we found with highest poly-P production, variations in ppk expression were linked to growth conditions and presence of phosphate in the medium. Moreover, the strain produced poly-P in presence of breast milk and lacto-N-tetraose increased the amount of poly-P synthesized. Compared to KABP042 supernatants low in poly-P, exposure of Caco-2 cells to KABP042 supernatants rich in poly-P resulted in decreased epithelial permeability and increased barrier resistance, induction of epithelial protecting factors such as HSP27 and enhanced expression of tight junction protein genes. These results highlight the role of bifidobacteria-derived poly-P as a strain-dependent functional factor acting on epithelial integrity.

The impact of metallic nanoparticles on gut fermentation processes: An integrated metabolomics and metagenomics approach following an in vitro digestion and fecal fermentation model

Metallic nanoparticles (MNPs) are becoming widespread environmental contaminants. They are currently added to several food preparations and cause a fast-growing concern for human health. The present work aims to assess the impact of zinc oxide (ZnO), titanium dioxide (TiO₂), and silver (Ag) nanoparticles (NPs) on the human gut metabolome and microbiome. Water samples spiked with two different concentrations of each MNPs were subjected to in-vitro gastrointestinal digestion and in-vitro large intestine fermentation. The effects of the treatments were determined through 16 S amplicon sequencing and untargeted metabolomics. Multi-omics data integration was then applied to correlate the two datasets. MNPs treatments modulated the microbial genera Bifidobacterium, Sutterella, Escherichia and Bacteroides. The treatments, especially the lower concentrations of Ag and ZnO, caused modulation of indole derivatives, peptides, and metabolites related to protein metabolism in the large intestine. Notably, these metabolites are implicated in ulcerative colitis and inflammatory bowel disease. TiO₂ NPs treatment in all concentrations increased E.coli relative abundance and decreased the abundance of B. longum. Moreover, for TiO2_, an enrichment in proinflammatory lipid mediators of arachidonic acid metabolites, such as prostaglandin E2 and leukotrienes B4, was detected. For all metals except TiO_2, low NP concentrations promoted differentiated profiles, thus suggesting that MNPs aggregation can limit adverse effects on living cells.

Detection of colonization capacity of probiotic Bifidobacterium breve CCFM1025 in the human gut

Aim: To detect the gut colonization capacity of Bifidobacterium breve CCFM1025 with clinical antidepressant-like effects. Materials & methods: A unique gene sequence of B. breve CCFM1025 was discovered based on the genome analysis of 104 B. breve strains and a strain-specific primer (1025T5) was designed. In vitro and in vivo samples were used to validate the specificity and quantitative capability of this primer in the PCR system. Results: Quantitative PCR using strain-specific primers enabled absolute quantification of CCFM1025 in fecal samples within 104-1010 cells/g (R2 >0.99). CCFM1025 remained highly detectable in volunteer feces 14 days after cessation of administration, demonstrating its favorable colonization characteristics. Conclusion: CCFM1025 can colonize the healthy human gut.

The Effect of Probiotic Supplementation on the Gut-Brain Axis in Psychiatric Patients

The pathophysiology of several psychiatric diseases may entail disturbances in the hypothalamic-pituitary-adrenal (HPA) axis and metabolic pathways. Variations in how these effects present themselves may be connected to individual variances in clinical symptoms and treatment responses, such as the observation that a significant fraction of participants do not respond to current antipsychotic drugs. A bidirectional signaling pathway between the central nervous system and the gastrointestinal tract is known as the microbiota-gut-brain axis. The large and small intestines contain more than 100 trillion microbial cells, contributing to the intestinal ecosystem's incredible complexity. Interactions between the microbiota and intestinal epithelium can alter brain physiology and affect mood and behavior. There has recently been a focus on how these relationships impact mental health. According to evidence, intestinal microbiota may play a role in neurological and mental illnesses. Intestinal metabolites of microbial origin, such as short-chain fatty acids, tryptophan metabolites, and bacterial components that might stimulate the host's immune system, are mentioned in this review. We aim to shed some on the growing role of gut microbiota in inducing/manipulating several psychiatric disorders, which may pave the way for novel microbiota-based therapies.

Effects of Mixed Nut Consumption on Blood Glucose, Insulin, Satiety, and the Microbiome in a Healthy Population: A Pilot Study

Nuts contain many health-promoting nutrients, fiber, and phytochemicals. Nut consumption has been reported to improve several chronic disease risk factors. Most studies to date have investigated single variety nut consumption. A nut mixture may offer a more diverse array of nutrients over single variety nuts. The primary outcome of this study was to examine the effects of mixed nut consumption on postprandial glucose, insulin, and satiety in healthy young adults. Exploratory outcomes include the effects of daily nut consumption on stool microbiome and bowel movement patterns. Twenty participants were randomized to consume either 42 g of mixed nuts or 46 g of potato chips daily for 3 weeks. Mixed nut consumption did not alter postprandial blood glucose and insulin, while potato chip consumption increased glucose and insulin (P < .05). There were no significant differences in fasting blood glucose or insulin for either snack after 3 weeks of daily consumption. Both snacks increased satiety while there were no significant differences in body weight, body fat, blood pressure, waist-to-hip ratio, or anxiety. After 3 weeks of snack consumption, both groups significantly reduced straining during bowel movements while the mixed nut group slightly increased stool amount. There were no significant changes in microbiome composition for either group; however, there was a nonsignificant trend toward increased Firmicutes to Bacteroidetes ratio in the potato chip group and an opposite trend in the mixed nut group. The results of this study suggest that mixed nuts are a healthy alternative for blood sugar control. The study was registered at ClinicalTrials.gov, Number: NCT03375866.

Fermented soy beverages as vehicle of probiotic lactobacilli strains and source of bioactive isoflavones: A potential double functional effect

Soy beverages can be a source of bioactive isoflavones, with potential human health benefits. In this work, the suitability of three Lacticaseibacillus and three Bifidobacterium probiotic strains as functional starters for soy beverage fermentation were evaluated, alongside with the effect of refrigerated storage on the viability of the strains and the isoflavone composition of the fermented beverages. The three bifidobacteria strains suffered a decrease in their viability during refrigeration and only Bifidobacterium breve INIA P734 produced high concentrations of bioactive isoflavones. Meanwhile, L. rhamnosus GG and L. rhamnosus INIA P344 produced high levels of aglycones and, with L. paracasei INIA P272, maintained their viability during the refrigeration period, constituting promising starters to obtain functional soy beverages that could gather the benefits of the bioactive isoflavone aglycones and the probiotic strains. Moreover, the three lactobacilli caused an increase in the antioxidant capacity of the fermented beverages, which was maintained over the refrigerated storage.

Protective effect of Bifidobacterium longum BB536 against nausea caused by pirfenidone in a mouse model of pellagra

Pellagra is caused by abnormal intake and/or use of nicotinic acid and is known in part to be induced by the use of medications such as isoniazid or pirfenidone. We previously investigated atypical phenotypes of pellagra, such as nausea, using a mouse model of pellagra and found that gut microbiota play an important role in the development of these phenotypes. Here, we investigated the effect of Bifidobacterium longum BB536 on pellagra-related nausea caused by pirfenidone in our mouse model. Our pharmacological data indicated that pirfenidone (PFD) causes modulation of the gut microbiota profile, which appeared to play an important role in the development of pellagra-related nausea. A gut microbiota-mediated protective effect of B. longum BB536 against nausea caused by PFD was also identified. Finally, the urinary ratio of nicotinamide/N-methylnicotinamide was shown to be a biomarker of pellagra-like adverse effects induced by PFD, and it may contribute to the prevention of these effects in patients with idiopathic pulmonary fibrosis.

Usefulness of Bifidobacterium longum BB536 in Elderly Individuals With Chronic Constipation: A Randomized Controlled Trial

INTRODUCTION

Few reports exist regarding the therapeutic effects of probiotics on chronic constipation in elderly individuals. This study evaluated the effects of Bifidobacterium longum BB536 in elderly individuals with chronic constipation.

METHODS

This was a randomized, double-blind placebo-controlled, parallel-group superiority trial in Japan (UMIN 000033031). Eighty older adults diagnosed with chronic constipation were randomly assigned (1:1) to receive either probiotics ( B. longum BB536, 5 × 10 10 colony-forming unit, n = 39) or placebo (n = 41) once daily for up to 4 weeks. The severity of constipation was evaluated using the Constipation Scoring System. The primary end point was the difference in the changes from baseline in the constipation scoring system total score between the 2 groups at week 4.

RESULTS

A total of 79 patients (mean age of 77.9 years), including 38 patients in the BB536 group and 41 in the placebo group, completed the study. The primary end point was not significant ( P = 0.074), although there was significant improvement ( P < 0.01) in the BB536 group from baseline to week 4, but there were no significant changes in the placebo group. There was a significant difference and a tendency toward a difference in the changes from baseline on the stool frequency ( P = 0.008) and failure of evacuation ( P = 0.051) subscales, respectively, at week 4 between the 2 groups. Few adverse events related to the probiotics were observed.

DISCUSSION

The primary end points were not significant. However, probiotic supplementation significantly improved bowel movements. These results suggest that B. longum BB536 supplementation is safe and partially effective for improving chronic constipation in elderly individuals.

The Crosstalk between Intestinal Epithelial Cells and Mast Cells Is Modulated by the Probiotic Supplementation in Co-Culture Models

The intestinal epithelium constitutes a selectively permeable barrier between the internal and external environment that allows the absorption of nutrients, electrolytes, and water, as well as an effective defense against intraluminal bacteria, toxins, and potentially antigenic material. Experimental evidence suggest that intestinal inflammation is critically dependent on an imbalance of homeostasis between the gut microbiota and the mucosal immune system. In this context, mast cells play a crucial role. The intake of specific probiotic strains can prevent the development of gut inflammatory markers and activation of the immune system. Here, the effect of a probiotic formulation containing L. rhamnosus LR 32, B. lactis BL04, and B. longum BB 536 on intestinal epithelial cells and mast cells was investigated. To mimic the natural host compartmentalization, Transwell co-culture models were set up. Co-cultures of intestinal epithelial cells interfaced with the human mast cell line HMC-1.2 in the basolateral chamber were challenged with lipopolysaccharide (LPS), and then treated with probiotics. In the HT29/HMC-1.2 co-culture, the probiotic formulation was able to counteract the LPS-induced release of interleukin 6 from HMC-1.2, and was effective in preserving the epithelial barrier integrity in the HT29/Caco-2/ HMC-1.2 co-culture. The results suggest the potential therapeutic effect of the probiotic formulation.

Impact of tuberculosis disease on human gut microbiota: a systematic review

INTRODUCTION

This systematic review evaluates the gut microbiota (GM) status in tuberculosis (TB) patients compared to healthy volunteers due to the disease or its treatment.

AREAS COVERED

We conducted a systematic review of all articles published in PubMed, Web of Science, and Embase that assessed the impact of TB disease and anti-tubercular therapy (ATT) on GM from inception till January 2022 (Protocol registration number in PROSPERO: CRD42021261884). Regarding the microbial diversity indices and taxonomy, we found a significant difference in GM status between the TB and healthy control (HC) groups. We found an overabundance of Phylum Proteobacteria and depletion of some short-chain fatty acid-producing bacteria genera like Bifidobacteria, Roseburia, and Ruminococcus in the TB group. We found that ATT exacerbates the degree of dysbiosis caused by Mycobacteria tuberculosis disease.

EXPERT OPINION

The modulation of GM in TB patients in clinical practice may serve as a promising target to reverse the dysbiosis caused. Moreover, this can optimistically change the TB treatment outcome. We expect that appropriate probiotic supplementation with antimycobacterial treatment during tuberculosis disease will help stabilize the GM throughout the treatment phase and protect the GM from dysbiosis.

Probiotic Yoghurt Made from Milk of Ewes Fed a Diet Supplemented with Spirulina platensis or Fish Oil

Purpose

Yoghurt is a widely consumed dairy product around the world. It has healing properties and characteristics that are important for human health. Our goal was to see how using ewes' milk fed Spirulina platensis (SP) or fish oil (FO)-supplemented diets affected the chemical, physical, and nutritional properties of yoghurt, as well as the activity and survival of starter and probiotic bacteria during storage.

Methods

The collected milk from each ewe group was preheated to 65 °C and homogenized in a laboratory homogenizer, then heated to 90 °C for 5 min, cooled to 42 °C, and divided into two equal portions. The first portion was inoculated with 2.0% mixed starter culture (Lactobacillus bulgaricus and Streptococcus thermophilus, 1:1), whereas the second was inoculated with 2% mixed starter culture and 1% Bifidobacterium longum as a probiotic bacteria.

Results

SP yoghurt had the highest levels of short chain-FA, medium chain-FA, mostly C10:0, and long chain-FA, namely C16:0, C18:2 and the lowest levels of C18:0 and C18:1, followed by FO yoghurt. The addition of SP or FO to ewes' diets resulted in yoghurt with higher viable counts of L. bulgaricus and S. thermophilus, which were still >107 cfu/g at the end of storage, as well as a higher level of acetaldehyde content (P<0.05) as a flavor compound, than the control (C) yoghurt. The viscosity of SP yoghurt was higher than that of FO and C yoghurt; the difference was not significant. The addition of B. longum, a probiotic bacteria, to all yoghurt samples, improved antioxidant activities, particularly against ABTS• radicals, but reduced SP yoghurt viscosity. When B. longum was added, acetaldehyde content increased from 39.91, 90.47, and 129.31 μmol/100g in C, FA, and SP yoghurts to 46.67, 135.55, and 144.1 μmol/100g in probiotic C, FA, and SP yoghurts, respectively. There was no significant difference in sensory qualities among all the yoghurt samples during all storage periods.

Conclusions

Supplementing the ewes' diets with Spirulina platensis or fish oil can change the fatty acid composition of the resulting yoghurt. The starter culture's activity, flavor compounds, and some chemical, physical, and antioxidant properties of milk produced from these diets can all be improved, particularly in yoghurt treated with probiotic bacteria (B. longum).

The Potential Role of Human Milk Oligosaccharides in Irritable Bowel Syndrome

Irritable Bowel Syndrome (IBS) is the most common gastrointestinal (GI) disorder in Western populations and therefore a major public health/economic concern. However, despite extensive research, psychological and physiological factors that contribute to the aetiology of IBS remain poorly understood. Consequently, clinical management of IBS is reduced to symptom management through various suboptimal options. Recent evidence has suggested human milk oligosaccharides (HMOs) as a potential therapeutic option for IBS. Here, we review literature concerning the role of HMOs in IBS, including data from intervention and in vitro trials. HMO supplementation shows promising results in altering the gut microbiota and improving IBS symptoms, for instance by stimulating bifidobacteria. Further research in adults is required into HMO mechanisms, to confirm the preliminary results available to date and recommendations of HMO use in IBS.

Isolation of Yeasts from Some Homemade Fermented Cow-Milk Products of Sikkim and Their Probiotic Characteristics

Dahi and chhurpi are the homemade, mildly acidic and mouthfeel fermented dairy products of Sikkim in India. Since yeasts co-exist among traditional fermented dairy foods, we believe that some species of yeasts may have some probiotic properties. Hence, the present study is aimed at screening some probiotic yeasts from dahi and chhurpi. A total of 3438 yeasts were isolated from 40 samples of dahi (1779 isolates) and 40 chhurpi (1659 isolates) and were preliminarily screened for probiotic properties on the basis of survival in low pH, resistance to bile salts and the percentage of hydrophobicity, out of which only 20 yeasts were selected for in vitro and genetic screening of probiotic properties. Saccharomyces cerevisiae DJT-2 and Debaryomyces prosopidis CPA-55 showed the highest hydrophobicity of 97.54% and 98.33%, respectively. S. cerevisiae DRC-42 and S. cerevisiae CGI-29 showed 93.88% and 91.69% auto-aggregation, respectively. All yeasts showed co-aggregation properties against pathogenic bacteria. Kluyveromyces marxianus DPA-41 and Pichia kudriavzevii CNT-3 showed excellent deconjugation activities. Probiotic genes for acid tolerance, bile tolerance, adhesion and antimicrobial activity were detected in S. cerevisiae DAO-17, K. marxianus DPA-41, S. cerevisiae CKL-10 and P. kudriavzevii CNT-3. Based on the results of in vitro and genetic screening of probiotic yeasts strains, S. cerevisiae DAO-17 (dahi), S. cerevisiae CKL-10 (chhurpi), P. kudriavzevii CNT-3 (chhurpi) and K. marxianus DPA-41(dahi) were selected as the potential probiotic yeasts.

Effect of a Bifidobacterium-Containing Acid-Resistant Microcapsule Formulation on Gut Microbiota: A Pilot Study

Approximately 10 Bifidobacterium species are known to inhabit the human intestinal tract. Bifidobacteria have been reported to possess a variety of probiotic benefits. However, when bifidobacteria are consumed internally as probiotics, the bacteria are killed by gastric acid. Therefore, we developed acid-resistant microcapsules containing Bifidobacterium breve M-16V and B. longum BB536, which are unaffected by gastric acid, and evaluated whether the microcapsule formulation increased the amount of bifidobacteria in the stool after administration compared with the powder formulation. The results revealed no significant difference in the percentage or number of B. longum between before and after administration of the powder or microcapsule formulation in children. By contrast, the bacterial count of B. breve was significantly increased after microcapsule formulation administration (1.5 × 10⁵ copies/g after administration versus 2.8 × 10⁴ copies/g before administration, p = 0.013). In addition, the increase in the bacterial count of B. breve in stools after administration of microcapsule formulation was approximately 1000-fold higher than that after powder formulation administration (p = 0.018). In conclusion, the results indicate that the microcapsule formulation is efficiently transferred to the large intestine without the adverse effects of gastric acidity in children.

Fermented Black Tea and Its Relationship with Gut Microbiota and Obesity: A Mini Review

Fermentation is one of the world’s oldest techniques for food preservation, nutrient enhancement, and alcohol manufacturing. During fermentation, carbohydrates such as glucose and starch are converted into other molecules, such as alcohol and acid, anaerobically through enzymatic action while generating energy for the microorganism or cells involved. Black tea is among the most popular fermented beverages; it is made from the dried tea leaves of the evergreen shrub plant known as Camellia sinensis. The adequate consumption of black tea is beneficial to health as it contains high levels of flavanols, also known as catechins, which act as effective antioxidants and are responsible for protecting the body against the development of illnesses, such as inflammation, diabetes, hypertension, cancer, and obesity. The prevalence of obesity is a severe public health concern associated with the incidence of various serious diseases and is now increasing, including in Malaysia. Advances in ‘omic’ research have allowed researchers to identify the pivotal role of the gut microbiota in the development of obesity. This review explores fermented black tea and its correlation with the regulation of the gut microbiota and obesity.

The synthesis of extracellular vesicles by the protistan parasite Blastocystis

Blastocystis is a genus of single-celled protist belonging to the stramenopile group. Prior studies have shown that isolates of Blastocystis subtype 7 (ST7) induced higher levels of intestinal epithelial cell damage and gut microbiota dysbiosis in comparison to other subtypes in in vivo and in vitro settings. Prior research has shown a link between gut dysbiosis and exposure to extracellular vesicles (EVs) produced by pathogenic microorganisms. This study demonstrates a protocol for the isolation of EVs from Blastocystis ST7 via ultracentrifugation. Nanoparticle tracking analysis and transmission electron microscopy were used to assess EV size and morphology. The protein content of isolated EVs was assessed by mass spectrophotometry and the presence of EV markers were evaluated by Western blotting. Finally, the EVs were cocultured with prominent human gut microbiome species to observe their effect on prokaryote growth. Our data shows that Blastocystis ST7 secretes EVs that are similar in morphology to previously characterized EVs from other organisms and that these EVs contain a limited yet unique protein cargo with functions in host-parasite intercellular communication and cell viability. This cargo may be involved in mediating the effects of Blastocystis on its surrounding environment.

Cocoa seeds and chocolate products interaction with gut microbiota; mining microbial and functional biomarkers from mechanistic studies, clinical trials and 16S rRNA amplicon sequencing

In recent years, gut microbiome has evolved as a focal point of interest with growing recognition that a well-balanced gut microbiota is highly relevant to an individual's health status. The present review provides a mechanistic insight on the effects of cocoa chemicals on the gut microbiome and further reveals in silico biomarkers, taxonomic and functional features that distinguish gut microbiome of cocoa consumers and controls by using 16S rRNA gene sequencing data. The polyphenols in cocoa can change the gut microbiota either by inhibiting the growth of pathogenic bacteria in the gut such as Clostridium perfringens or by increasing the growth of beneficial microbiota in the gut such as Lactobacillus and Bifidobacterium. This paper demonstrates the holistic effect of gut microbiota on cocoa chemicals and how it impacts human health. We present herein the first comprehensive review and analysis of how raw and roasted cocoa and its products can specifically influence gut homeostasis, and likewise, how microbiota metabolizes cocoa chemicals. In addition to that, our 16S rRNA amplicon sequencing analysis revealed that the flavone and flavonols metabolism, aminobenzoate degradation and fatty acid elongation pathways represent the three most important signatures of microbial functions associated with cocoa consumption.

A Multi-Strain Probiotic Formulation Improves Intestinal Barrier Function by the Modulation of Tight and Adherent Junction Proteins

In healthy individuals, tight junction proteins (TJPs) maintain the integrity of the intestinal barrier. Dysbiosis and increased intestinal permeability are observed in several diseases, such as inflammatory bowel disease. Many studies highlight the role of probiotics in preventing intestinal barrier dysfunction. The present study aims to investigate the effects of a commercially available probiotic formulation of L. rhamnosus LR 32, B. lactis BL 04, and B. longum BB 536 (Serobioma, Bromatech s.r.l., Milan, Italy) on TJPs and the integrity of the intestinal epithelial barrier, and the ability of this formulation to prevent lipopolysaccharide-induced, inflammation-associated damage. An in vitro model of the intestinal barrier was developed using a Caco-2 cell monolayer. The mRNA expression levels of the TJ genes were analyzed using real-time PCR. Changes in the amounts of proteins were assessed with Western blotting. The effect of Serobioma on the intestinal epithelial barrier function was assessed using transepithelial electrical resistance (TEER) measurements. The probiotic formulation tested in this study modulates the expression of TJPs and prevents inflammatory damage. Our findings provide new insights into the mechanisms by which probiotics are able to prevent damage to the gut epithelial barrier.

The influence of perceived stress on the human microbiome

Objective

Microbial dysbiosis, a shift from commensal to pathogenic microbiota, is often associated with mental health and the gut–brain axis, where dysbiosis in the gut may be linked to dysfunction in the brain. Many studies focus on dysbiosis induced by clinical events or traumatic incidents; however, many professions in austere or demanding environments may encounter continuously compounded stressors. This study seeks to explore the relationship between microbial populations and stress, both perceived and biochemical.

Results

Eight individuals enrolled in the study to provide a longitudinal assessment of the impact of stress on gut health, with four individuals providing enough samples for analysis. Eleven core microbial genera were identified, although the relative abundance of these genera and other members of the microbial population shifted over time. Although our results indicate a potential relationship between perceived stress and microbial composition of the gut, no association with biochemical stress was observed. Increases in perceived stress seem to elucidate a change in potentially beneficial Bacteroides, with a loss in Firmicutes phyla. This shift occurred in multiple individuals, whereas using cortisol as a stress biomarker showed contradictory responses. These preliminary data provide a potential mechanism for gut monitoring, while identifying targets for downstream modulation.

Elucidating the role of the gut microbiota in the physiological effects of dietary fiber

BACKGROUND

Dietary fiber is an integral part of a healthy diet, but questions remain about the mechanisms that underlie effects and the causal contributions of the gut microbiota. Here, we performed a 6-week exploratory trial in adults with excess weight (BMI: 25-35 kg/m2) to compare the effects of a high-dose (females: 25 g/day; males: 35 g/day) supplement of fermentable corn bran arabinoxylan (AX; n = 15) with that of microbiota-non-accessible microcrystalline cellulose (MCC; n = 16). Obesity-related surrogate endpoints and biomarkers of host-microbiome interactions implicated in the pathophysiology of obesity (trimethylamine N-oxide, gut hormones, cytokines, and measures of intestinal barrier integrity) were assessed. We then determined whether clinical outcomes could be predicted by fecal microbiota features or mechanistic biomarkers.

RESULTS

AX enhanced satiety after a meal and decreased homeostatic model assessment of insulin resistance (HOMA-IR), while MCC reduced tumor necrosis factor-α and fecal calprotectin. Machine learning models determined that effects on satiety could be predicted by fecal bacterial taxa that utilized AX, as identified by bioorthogonal non-canonical amino acid tagging. Reductions in HOMA-IR and calprotectin were associated with shifts in fecal bile acids, but correlations were negative, suggesting that the benefits of fiber may not be mediated by their effects on bile acid pools. Biomarkers of host-microbiome interactions often linked to bacterial metabolites derived from fiber fermentation (short-chain fatty acids) were not affected by AX supplementation when compared to non-accessible MCC.

CONCLUSION

This study demonstrates the efficacy of purified dietary fibers when used as supplements and suggests that satietogenic effects of AX may be linked to bacterial taxa that ferment the fiber or utilize breakdown products. Other effects are likely microbiome independent. The findings provide a basis for fiber-type specific therapeutic applications and their personalization.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT02322112 , registered on July 3, 2015. Video Abstract.

Bifidobacterium spp. as functional foods: A review of current status, challenges, and strategies

Members of Bifidobacterium are among the first microbes to colonize the human intestine naturally, their abundance and diversity in the colon are closely related to host health. Recently, the gut microbiota has been gradually proven to be crucial mediators of various metabolic processes between the external environment and the host. Therefore, the health-promoting benefits of Bifidobacterium spp. and their applications in food have gradually been widely concerned. The main purpose of this review is to comprehensively introduce general features, colonization methods, and safety of Bifidobacterium spp. in the human gut, highlighting its health benefits and industrial applications. On this basis, the existing limitations and scope for future research are also discussed. Bifidobacteria have beneficial effects on the host's digestive system, immune system, and nervous system. However, the first prerequisite for functioning is to have enough live bacteria before consumption and successfully colonize the colon after ingestion. At present, strain breeding, optimization (e.g., selecting acid and bile resistant strains, adaptive evolution, high cell density culture), and external protection technology (e.g., microencapsulation and protectants) are the main strategies to address these challenges in food application.

Different Alterations in Gut Microbiota between Bifidobacterium longum and Fecal Microbiota Transplantation Treatments in Propionic Acid Rat Model of Autism

Autism spectrum disorders (ASD) consist of a range of neurodevelopmental conditions accompanied by dysbiosis of gut microbiota. Therefore, a number of microbiota manipulation strategies were developed to restore their balance. However, a comprehensive comparison of the various methods on gut microbiota is still lacking. Here, we evaluated the effect of Bifidobacterium (BF) treatment and fecal microbiota transplantation (FT) on gut microbiota in a propionic acid (PPA) rat model of autism using 16S rRNA sequencing. Following PPA treatment, gut microbiota showed depletion of Bacteroidia and Akkermansia accompanied by a concomitant increase of Streptococcus, Lachnospiraceae, and Paraeggerthella. The dysbiosis was predicted to cause increased levels of porphyrin metabolism and impairments of acyl-CoA thioesterase and ubiquinone biosynthesis. On the contrary, BF and FT treatments resulted in a distinct increase of Clostridium, Bifidobacterium, Marvinbryantia, Butyricicoccus, and Dorea. The taxa in BF group positively correlated with vitamin B12 and flagella biosynthesis, while FT mainly enriched flagella biosynthesis. In contrast, BF and FT treatments negatively correlated with succinate biosynthesis, pyruvate metabolism, nitrogen metabolism, beta-Lactam resistance, and peptidoglycan biosynthesis. Therefore, the present study demonstrated that BF and FT treatments restored the PPA-induced dysbiosis in a treatment-specific manner.

The role of the gut microbiota and nutrition on spatial learning and spatial memory: a mini review based on animal studies

The gut-brain axis is believed to constitute a bidirectional communication mechanism that affects both mental and digestive processes. Recently, the role of the gut microbiota in cognitive performance has been the focus of much research. In this paper, we discuss the effects of gut microbiota and nutrition on spatial memory and learning. Studies have shown the influence of diet on cognitive capabilities such as spatial learning and memory. It has been reported that a high-fat diet can alter gut microbiota which subsequently leads to changes in spatial learning and memory. Some microorganisms in the gut that can significantly affect spatial learning and memory are Akkermansia muciniphila, Bifidobacterium, Lactobacillus, Firmicutes, Bacteroidetes, and Helicobacter pylori. For example, a reduction in the amount of A. muciniphila in the gut leads to increased intestinal permeability and induces immune response in the brain which then negatively affects cognitive performances. We suggest that more studies should be carried out regarding the indirect effects of nutrition on cognitive activities via alteration in gut microbiota.

Antidiabetic Effects of Bifidobacterium longum subsp. longum BL21 through Regulating Gut Microbiota Structure in Type 2 Diabetic Mice

Bifidobacterium longum subsp. longum BL21 (BL21) possess hypoglycemic activity, but its anti-diabetic mechanism has rarely been illustrated. In the present work, the effect of BL21 on type 2 diabetes mellitus...

Chronic opioid use modulates human enteric microbiota and intestinal barrier integrity

Over the past three decades the United States has experienced a devastating opioid epidemic. One of the many debilitating side effects of chronic opioid use is opioid-induced bowel dysfunction. We investigated the impact of methadone maintenance treatment (MMT) on the gut microbiome, the gut bacterial metabolite profile, and intestinal barrier integrity. An imbalance in key bacterial communities required for production of short-chain fatty acids (SCFAs), mucus degradation, and maintenance of barrier integrity was identified. Consistent with dysbiosis, levels of fecal SCFAs were reduced in MMT. We demonstrated that metabolites synthesized by Akkermansia muciniphila modulate intestinal barrier integrity in vitro by strengthening the pore pathway and regulating tight junction protein expression. This study provides essential information about the therapeutic potential of A. muciniphila and warrants development of new clinical strategies that aim to normalize the gut microbiome in individuals affected by chronic opioid use.

Differences in the gut microbiota composition of rats fed with soybean protein and their derived peptides

Current studies regarding the effect of different nitrogen sources on gut microbiota have thus far disregarded the ability of probiotics and coliforms to compete for protein. This study aimed to investigate the differences in the utilization of soybean protein (SPro) and its derived peptides (SPep) by the gut microbiota of Sprague Dawley (SD) rats. The SPro and SPep prepared in this study showed extensive SPro molecular weight distribution, while that of SPep was minimal, ranging between 150 and 1000 Da and primarily consisting of two to five amino acids. The cecum microflora composition of the rats was determined via 16S rDNA amplicon sequencing, showing that the SPro and SPep significantly increased the abundance and uniformity of the gut microbiota after 35 days of feeding. The Firmicutes/Bacteroidetes (F/B) ratios of the SPep, SPro, and casein groups were 2.49 ± 0.60, 2.98 ± 1.12, and 2.59 ± 0.74, respectively. Although the rats fed with SPro and SPep displayed similar gut microbiome structures, SPep significantly promoted Lactobacillus and Phascolarctobacterium growth. The results showed that SPep significantly increased the diversity of the gut microbiota and elevated the probiotic proportion. PRACTICAL APPLICATION: SPro and SPep are two nutritious and high-quality nitrogen sources. The results showed that SPro and SPep regulated the structure of gut microbiota in rats, and the effect of SPep was better. This study provides a theoretical basis for developing SPep functional foods able to regulate gut microbiota and maintain health.

Fecal Transplant and Bifidobacterium Treatments Modulate Gut Clostridium Bacteria and Rescue Social Impairment and Hippocampal BDNF Expression in a Rodent Model of Autism

Autism is associated with gastrointestinal dysfunction and gut microbiota dysbiosis, including an overall increase in Clostridium. Modulation of the gut microbiota is suggested to improve autistic symptoms. In this study, we explored the implementation of two different interventions that target the microbiota in a rodent model of autism and their effects on social behavior: the levels of different fecal Clostridium spp., and hippocampal transcript levels. Autism was induced in young Sprague Dawley male rats using oral gavage of propionic acid (PPA) for three days, while controls received saline. PPA-treated animals were divided to receive either saline, fecal transplant from healthy donor rats, or Bifidobacterium for 22 days, while controls continued to receive saline. We found that PPA attenuated social interaction in animals, which was rescued by the two interventions. PPA-treated animals had a significantly increased abundance of fecal C. perfringens with a concomitant decrease in Clostridium cluster IV, and exhibited high hippocampal Bdnf expression compared to controls. Fecal microbiota transplantation or Bifidobacterium treatment restored the balance of fecal Clostridium spp. and normalized the level of Bdnf expression. These findings highlight the involvement of the gut-brain axis in the etiology of autism and propose possible interventions in a preclinical model of autism.

Bifidobacterium Longum: Protection against Inflammatory Bowel Disease

The prevalence of inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD), increases gradually worldwide in the past decades. IBD is generally associated with the change of the immune system and gut microbiota, and the conventional treatments usually result in some side effects. Bifidobacterium longum, as colonizing bacteria in the intestine, has been demonstrated to be capable of relieving colitis in mice and can be employed as an alternative or auxiliary way for treating IBD. Here, the mechanisms of the Bifidobacterium longum in the treatment of IBD were summarized based on previous cell and animal studies and clinical trials testing bacterial therapies. This review will be served as a basis for future research on IBD treatment.

Local intestinal microbiota response and systemic effects of feeding black soldier fly larvae to replace soybean meal in growing pigs

Black soldier fly (Hermetia illucens; BSF) larvae as dietary protein source have the ability to deliver nutrients and could possess functional properties that positively support animal productivity and health. More knowledge, however, is needed to assess the impact of feeding a BSF based diet on gut and animal health. Sixteen post-weaned male pigs were randomly assigned to two groups and fed for three weeks with iso-caloric and iso-proteinaceous experimental diets prepared with either soybean meal (SBM) as reference protein source or with BSF as single source of dietary protein. At the end of the trial, the pigs were sacrificed to collect relevant digesta, gut tissue and blood samples to study changes induced by the dietary treatments using ~ omics based analyses. Inclusion of BSF in the diet supports the development of the intestinal microbiome that could positively influence intestinal health. By amine metabolite analysis, we identified two metabolites i.e. sarcosine and methionine sulfoxide, in plasma that serve as markers for the ingestion of insect based ingredients. BSF seems to possess functional properties indicated by the appearance of alpha-aminobutyric acid and taurine in blood plasma of pigs that are known to induce health beneficial effects.

Different Bifidobacterium bifidum strains change the intestinal flora composition of mice via different mechanisms to alleviate loperamide-induced constipation

Constipation is a condition with a high prevalence rate worldwide and may occur in men and women of any age. Bifidobacterium bifidum has been shown to have a relieving effect on constipation, but the underlying mechanism is still unknown. This study explored the effects of gavage of three strains of B. bifidum (CCFM668, FHNFQ25M12 and FXJCJ32M2) from different sources in mice with loperamide-induced constipation. After 38 days of intervention, B. bifidum CCFM668, FHNFQ25M12 and FXJCJ32M2 showed the ability to modify the levels of gastrointestinal active peptides and promote the expression of 5-hydroxytryptamine (5-HT or serotonin) receptor 4 (5-HT4R), thereby promoting small intestinal peristalsis. The strains could also effectively increase the thickness of the colonic mucosa. However, what was different from previous studies was that these results were independent of the levels of short-chain fatty acids (SCFAs) and 5-HT. Further analysis of the intestinal flora revealed that the relative abundances of the genera Faecalibaculum and Ruminococcaceae_UCG_014 in the constipated mice increased significantly, whereas that of Erysipelatoclostridium decreased. A correlation analysis between the intestinal flora and evaluated gastrointestinal indicators demonstrated that the relative abundances of the genera Anaerotruncus, Angelakisella, Erysipelatoclostridium and Ruminococcaceae_UCG_014 were negatively correlated with the levels of gastrointestinal active peptides. B. bifidum FXJCJ32M2 can increase the relative abundances of Turicibacter and Dubosiella, and this was positively correlated with the expression of aquaporin 8 and vasoactive intestinal peptide receptor 1 but could not effectively alleviate faecal dryness or promote colonic motility. These findings suggest that B. bifidum shows significant intraspecific differences in the remission mechanism and provides a theoretical basis for subsequent population experiments and personalised treatment for constipation.

Identification of the key characteristics of Bifidobacterium longum strains for the alleviation of ulcerative colitis

Bifidobacterium longum (B. longum) species are widely used to prevent and treat ulcerative colitis (UC). In this study, phylogenetic and pan-genomic characterization of 122 B. longum strains was performed on the basis of 936 core genes; among these, four strains from different branches of the phylogenetic tree were selected for an evaluation of anti-inflammatory and immune modulatory activities in a DSS-induced colitis mouse model. Among the tested B. longum strains (B. longum FBJ20M1, B. longum FGDLZ8M1, B. longum FGSZY16M3, and B. longum FJSWXJ2M1), B. longum FGDLZ8M1 was found to most effectively alleviate colitis by reducing the expression of pro-inflammatory cytokines, restoring the colon length, and maintaining the mucosal integrity. The anti-inflammatory mechanisms of B. longum FGDLZ8M1 were related to the inhibition of NF-κB signaling. Genomic analysis indicated that these protective effects of B. longum FGDLZ8M1 may be related to specific genes associated with carbohydrate transport and metabolism and defense mechanisms (e.g., tolerance to bile salts and acids). Correlation analysis indicated that gastrointestinal transit tolerance was the most strongly associated factor. Our findings may contribute to the rapid screening of lactic acid bacterial strains with UC-alleviating effects.

Probiotics in the dairy industry-Advances and opportunities

The past two decades have witnessed a global surge in the application of probiotics as functional ingredients in food, animal feed, and pharmaceutical products. Among food industries, the dairy industry is the largest sector where probiotics are employed in a number of dairy products including sour/fermented milk, yogurt, cheese, butter/cream, ice cream, and infant formula. These probiotics are either used as starter culture alone or in combination with traditional starters, or incorporated into dairy products following fermentation, where their presence imparts many functional characteristics to the product (for instance, improved aroma, taste, and textural characteristics), in addition to conferring many health-promoting properties. However, there are still many challenges related to the stability and functionality of probiotics in dairy products. This review highlights the advances, opportunities, and challenges of application of probiotics in dairy industries. Benefits imparted by probiotics to dairy products including their role in physicochemical characteristics and nutritional properties (clinical and functional perspective) are also discussed. We transcend the traditional concept of the application of probiotics in dairy products and discuss paraprobiotics and postbiotics as a newly emerged concept in the field of probiotics in a particular relation to the dairy industry. Some potential applications of paraprobiotics and postbiotics in dairy products as functional ingredients for the development of functional dairy products with health-promoting properties are briefly elucidated.