Fructooligosaccharides and galactooligosaccharides improve hepatic steatosis via gut microbiota-brain axis modulation.

Studies have shown that gut dysbiosis is associated with the steatotic liver disease associated with metabolic dysfunction (MALSD) and its severity. This study evaluated the effects of two commercially available prebiotics fructooligosaccharides (FOS) and galactooligosaccharides(GOS) on hepatic adipogenesis, inflammation, and gut microbiota in high-fat diet-induced MALSD. The results indicated that FOS and GOS effectively reduced insulin resistance, hyperglycaemia, triglyceridemia, cholesterolaemia, and IL-1ß serum levels. Moreover, FOS and GOS modulated the lipogenic (SREBP-1c, ACC, and FAS) and lipolytic (ATGL) signalling pathways, and reduced inflammatory markers such as p-NFκB-65, IL-6, iNOS, COX-2, TNF-α, IL-1ß, and nitrotyrosine. FOS and GOS also enhanced the abundance of acetate producers' bacteria Bacteroides acidifaciens and Bacteroides dorei. FOS and GOS also induced positive POMC/GPR43 neurons at the arcuate nucleus, indicating hypothalamic signalling modulation. Our results suggest that FOS and GOS attenuated MALSD by reducing the hepatic lipogenic pathways and intestinal permeability through the gut microbiota-brain axis.

Bioengineered Wheat Arabinoxylan - Fostering Next-Generation Prebiotics Targeting Health-Related Gut Microbes.

Dietary prebiotic fibers play an important role in modulating gut microbiota by enhancing the abundance of beneficial microorganisms and their bioactive metabolites. However, dietary fibers are a structurally heterogeneous class of polysaccharides, varying in molar mass, branching patterns, and monosaccharide composition, which could influence their utilization by various gut microorganisms. The present study aimed to investigate the effects of molar mass and chemical structure of wheat arabinoxylan fiber (AX) on the growth and metabolism of two key gut resident bacteria (Faecalibacterium prausnitzii and Lacticaseibacillus rhamnosus LGG), which are linked to human health. For this purpose, low, medium, and high molar masses of AX (LAX, MAX, and HAX, respectively) were modified with specific α-arabinofuranosidases to leave only singly substituted, only doubly substituted, or unsubstituted xylose units. Almost all the modified AX samples showed a better prebiotic score than unmodified AX for different molar masses. The modified LAX exhibited a better prebiotic effect than HAX and MAX. In addition, LAX, with doubly substituted xylose units, exhibited the highest prebiotic potential and SCFA production by both microorganisms. Furthermore, AX, either singly or doubly substituted, had a consistent impact on L. rhamnosus growth, whereas AX, with all arabinose residues removed, had a greater impact on F. prausnitzii. These findings support the potential of bioengineered AX as next-generation prebiotics targeting health-related gut microbes.

[Summary of the 8th Symposium "Feeding the microbiota": prebiotics and probiotics]. / Synthèse du 8e symposium « Feeding the Microbiota ¼ : prébiotiques et probiotiques.

The microbiota represents all the microorganisms including viruses, bacteria, fungi, and parasites, that have a symbiotic relationship with their host and that are present in a particular system (or niche) of the human body such as the skin, the respiratory tract, the urogenital tract or the digestive tract. This paper is a narrative review of all talks given at the 8th edition of the « Feeding the Microbiota ¼ symposium organized at the Geneva University Hospitals. The symposium gathered 346 participants, both onsite and online, from 23 countries all-around the world. The main thematic of this edition focused on the composition of the gut microbiota as affected by prebiotics and postbiotics and their effects on various diseases.

Le microbiote représente l'ensemble des micro-organismes (virus, bactéries, champignons et parasites) qui ont une relation symbiotique avec leur hôte et qui sont présents dans un système particulier du corps humain comme la peau, les voies respiratoires et/ou uro-génitales ou encore le tube digestif. Cet article est une revue narrative des différentes thématiques exposées lors du 8e symposium « Feeding the Microbiota ¼ organisé aux HUG le 9 février 2023. L'événement a réuni 346 participants en présentiel et en ligne venant de 23 pays différents. La thématique de cette édition s'est focalisée sur les effets des prébiotiques et des probiotiques sur la composition du microbiote et dans le contexte de certaines maladies.

A Fungal Versatile GH10 Endoxylanase and Its Glycosynthase Variant: Synthesis of Xylooligosaccharides and Glycosides of Bioactive Phenolic Compounds.

The study of endoxylanases as catalysts to valorize hemicellulosic residues and to obtain glycosides with improved properties is a topic of great industrial interest. In this work, a GH10 ß-1,4-endoxylanase (XynSOS), from the ascomycetous fungus Talaromyces amestolkiae, has been heterologously produced in Pichia pastoris, purified, and characterized. rXynSOS is a highly glycosylated monomeric enzyme of 53 kDa that contains a functional CBM1 domain and shows its optimal activity on azurine cross-linked (AZCL)-beechwood xylan at 70 °C and pH 5. Substrate specificity and kinetic studies confirmed its versatility and high affinity for beechwood xylan and wheat arabinoxylan. Moreover, rXynSOS was capable of transglycosylating phenolic compounds, although with low efficiencies. For expanding its synthetic capacity, a glycosynthase variant of rXynSOS was developed by directed mutagenesis, replacing its nucleophile catalytic residue E236 by a glycine (rXynSOS-E236G). This novel glycosynthase was able to synthesize ß-1,4-xylooligosaccharides (XOS) of different lengths (four, six, eight, and ten xylose units), which are known to be emerging prebiotics. rXynSOS-E236G was also much more active than the native enzyme in the glycosylation of a broad range of phenolic compounds with antioxidant properties. The interesting capabilities of rXynSOS and its glycosynthase variant make them promising tools for biotechnological applications.

Characterization of Latilactobacillus curvatus MS2 isolated from Korean traditional fermented seafood and cholesterol reduction effect as synbiotics with isomalto-oligosaccharide in BALB/c mice.

This study investigated the properties of Latilactobacillus curvatus MS2 isolated from Korean traditional fermented seafood as probiotics and the effect of reducing cholesterol as a synbiotic with isomalto-oligosaccharide (IMO) in BALB/c mice. The isolated strain showed high resistance to acids and bile acids and exhibited a high DPPH scavenging capacity of 72.27 ± 0.38 %. In the intestinal adhesion test using HT-29 cells, the adhesion rate of MS2 was 17.10 ± 1.78 %, which was higher than the adhesion rate of the other investigated probiotics. MS2 showed good antimicrobial activity against food-borne pathogens, especially Staphylococcus aureus, S. epidermidis, Escherichia coli, and Vibrio vulnificus. This strain had high availability for IMO among the prebiotics of fructo-oligosaccharide, inulin and IMO. Oral administration of MS2 and IMO to BALB/c mice for 5 weeks resulted in a significant reduction in blood cholesterol levels by regulating liver lipid metabolism. These results suggest that the combination of MS2 and IMO has potential for application in functional foods.

Molecular and Cellular Mechanisms Influenced by Postbiotics.

In recent years, commensal bacteria colonizing the human body have been recognized as important determinants of health and multiple pathologic conditions. Among the most extensively studied commensal bacteria are the gut microbiota, which perform a plethora of functions, including the synthesis of bioactive products, metabolism of dietary compounds, and immunomodulation, both through attenuation and immunostimulation. An imbalance in the microbiota population, i.e., dysbiosis, has been linked to many human pathologies, including various cancer types and neurodegenerative diseases. Targeting gut microbiota and microbiome-host interactions resulting from probiotics, prebiotics, and postbiotics is a growing opportunity for the effective treatment of various diseases. As more research is being conducted, the microbiome field is shifting from simple descriptive analysis of commensal compositions to more molecular, cellular, and functional studies. Insight into these mechanisms is of paramount importance for understanding and modulating the effects that microbiota, probiotics, and their derivatives exert on host health.

Hidden Role of Gut Microbiome Dysbiosis in Schizophrenia: Antipsychotics or Psychobiotics as Therapeutics?

Schizophrenia is a chronic, heterogeneous neurodevelopmental disorder that has complex symptoms and uncertain etiology. Mounting evidence indicates the involvement of genetics and epigenetic disturbances, alteration in gut microbiome, immune system abnormalities, and environmental influence in the disease, but a single root cause and mechanism involved has yet to be conclusively determined. Consequently, the identification of diagnostic markers and the development of psychotic drugs for the treatment of schizophrenia faces a high failure rate. This article surveys the etiology of schizophrenia with a particular focus on gut microbiota regulation and the microbial signaling system that correlates with the brain through the vagus nerve, enteric nervous system, immune system, and production of postbiotics. Gut microbially produced molecules may lay the groundwork for further investigations into the role of gut microbiota dysbiosis and the pathophysiology of schizophrenia. Current treatment of schizophrenia is limited to psychotherapy and antipsychotic drugs that have significant side effects. Therefore, alternative therapeutic options merit exploration. The use of psychobiotics alone or in combination with antipsychotics may promote the development of novel therapeutic strategies. In view of the individual gut microbiome structure and personalized response to antipsychotic drugs, a tailored and targeted manipulation of gut microbial diversity naturally by novel prebiotics (non-digestible fiber) may be a successful alternative therapeutic for the treatment of schizophrenia patients.

Postbiotics, Metabolic Signaling, and Cancer.

Postbiotics are health-promoting microbial metabolites delivered as a functional food or a food supplement. They either directly influence signaling pathways of the body or indirectly manipulate metabolism and the composition of intestinal microflora. Cancer is the second leading cause of death worldwide and even though the prognosis of patients is improving, it is still poor in the substantial part of the cases. The preventable nature of cancer and the importance of a complex multi-level approach in anticancer therapy motivate the search for novel avenues of establishing the anticancer environment in the human body. This review summarizes the principal findings demonstrating the usefulness of both natural and synthetic sources of postbotics in the prevention and therapy of cancer. Specifically, the effects of crude cell-free supernatants, the short-chain fatty acid butyrate, lactic acid, hydrogen sulfide, and ß-glucans are described. Contradictory roles of postbiotics in healthy and tumor tissues are highlighted. In conclusion, the application of postbiotics is an efficient complementary strategy to combat cancer.

Microbiome Composition in Pediatric Populations from Birth to Adolescence: Impact of Diet and Prebiotic and Probiotic Interventions.

Diet is a key regulator of microbiome structure and function across the lifespan. Microbial colonization in the first year of life has been actively researched; however, studies during childhood are sparse. Herein, the impact of dietary intake and pre- and probiotic interventions on microbiome composition of healthy infants and children from birth to adolescence is discussed. The microbiome of breastfed infants has lower microbial diversity and richness, higher Proteobacteria, and lower Bacteroidetes and Firmicutes than those formula-fed. As children consume more complex diets, associations between dietary patterns and the microbiota emerge. Like adults, the microbiota of children consuming a Western-style diet is associated with greater Bacteroidaceae and Ruminococcaceae and lower Prevotellaceae. Dietary fibers and pre- or/and probiotics have been tested to modulate the gut microbiota in early life. Human milk oligosaccharides and prebiotics added to infant formula are bifidogenic and decrease pathogens. In children, prebiotics, such as inulin, increase Bifidobacterium abundance and dietary fibers reduce fecal pH and increase alpha diversity and calcium absorption. Probiotics have been administered to the mother during pregnancy and breastfeeding or directly to the infant/child. Findings on maternal probiotic administration on bacterial taxa are inconsistent. When given directly to the infant/child, some changes in individual taxa are observed, but rarely is overall alpha or beta diversity affected. Cesarean-delivered infants appear to benefit to a greater degree than those born vaginally. Infancy and childhood represent an opportunity to beneficially manipulate the microbiome through dietary or prebiotic interventions, which has the potential to affect both short- and long-term health outcomes.

Microbial-Based and Microbial-Targeted Therapies for Inflammatory Bowel Diseases.

Inflammatory bowel diseases (IBD), including Crohn's disease, ulcerative colitis, and pouchitis, are chronic, relapsing intestinal inflammatory disorders mediated by dysregulated immune responses to resident microbiota. Current standard therapies that block immune activation with oral immunosuppressives or biologic agents are generally effective, but each therapy induces a sustained remission in only a minority of patients. Furthermore, these approaches can have severe adverse events. Recent compelling evidence of a role of unbalanced microbiota (dysbiosis) driving immune dysfunction and inflammation in IBD supports the therapeutic rationale for manipulating the dysbiotic microbiota. Traditional approaches using currently available antibiotics, probiotics, prebiotics, and synbiotics have not produced optimal results, but promising outcomes with fecal microbiota transplant provide a proof of principle for targeting the resident microbiota. Rationally designed oral biotherapeutic products (LBPs) composed of mixtures of protective commensal bacterial strains demonstrate impressive preclinical results. Resident microbial-based and microbial-targeted therapies are currently being studied with increasing intensity for IBD primary therapy with favorable early results. This review presents current evidence and therapeutic mechanisms of microbiota modulation, emphasizing clinical studies, and outlines prospects for future IBD treatment using new approaches, such as LBPs, bacteriophages, bacterial function-editing substrates, and engineered bacteria. We believe that the optimal clinical use of microbial manipulation may be as adjuvants to immunosuppressive for accelerated and improved induction of deep remission and as potential safer solo approaches to sustained remission using personalized regimens based on an individual patient's microbial profile.

Proteomic study of Enterococcus durans LAB18S growing on prebiotic oligosaccharides.

This study evaluates the influence of prebiotic carbohydrates, namely fructooligosaccharides (FOS) and galactooligosaccharides (GOS), on the protein expression of Enterococcus durans LAB18S. The strain was cultivated in 10 g L-1 FOS, GOS or glucose (control) and cellular proteins were extracted for mass spectrometry analysis. A total of 771 proteins were identified and 135 E. durans proteins were validated by the Scaffold algorithm. The proteins were functionally categorized according to Gene Ontology terms. Both FOS and GOS were used as carbon source by E. durans LAB18S, upregulating the production of proteins that may be associated with intestinal mucosa adhesion, carbohydrate and nitrogen metabolism, and stress response. Cells grown with GOS showed an increased expression of the cell division protein divIVA, EF-Tu and glyceraldehyde 3-phosphate dehydrogenase that have been associated with epithelial cell adhesion. The use of FOS stimulated the production of proteins related to amino acid metabolism and energy conversion, and ClpX protein, which plays an important role in protein turnover. The results of this study indicate that FOS and GOS can be metabolized by E. durans and stimulate the microorganism to produce proteins related to some desirable characteristics for a probiotic strain.

Effectiveness of probiotics, prebiotics, and prebiotic-like components in common functional foods.

The bioactive ingredients in commonly consumed foods include, but are not limited to, prebiotics, prebiotic-like components, probiotics, and postbiotics. The bioactive ingredients in functional foods have also been associated with beneficial effects on human health. For example, they aid in shaping of gut microflora and promotion of immunity. These functional components also contribute in preventing serious diseases such as cardiovascular malfunction and tumorigenesis. However, the specific mechanisms of these positive influences on human health are still under investigation. In this review, we aim to emphasize the major contents of probiotics, prebiotics, and prebiotic-like components commonly found in consumable functional foods, and we present an overview of direct and indirect benefits they provide on human health. The major contributors are certain families of metabolites, specifically short-chain fatty acids and polyunsaturated fatty acids produced by probiotics, and prebiotics, or prebiotic-like components such as flavonoids, polyphenols, and vitamins that are found in functional foods. These functional ingredients in foods influence the gut microbiota by stimulating the growth of beneficial microbes and the production of beneficial metabolites that, in turn, have direct benefits to the host, while also providing protection from pathogens and maintaining a balanced gut ecosystem. The complex interactions that arise among functional food ingredients, human physiology, the gut microbiota, and their respective metabolic pathways have been found to minimize several factors that contribute to the incidence of chronic disease, such as inflammation oxidative stress.

Lactose and Bovine Milk Oligosaccharides Synergistically Stimulate B. longum subsp. longum Growth in a Simplified Model of the Infant Gut Microbiome.

Increasing awareness of the importance of a healthy Bifidobacterium-rich microbiome has led to a need for more knowledge on how different prebiotic carbohydrates specifically impact the infant microbiome, especially as a community instead of single bacterial targets. In this study, we combined proton nuclear magnetic resonance (1H NMR) metabolomics and molecular biology methods for quantification of bacteria to compare the prebiotic effect of bovine milk oligosaccharides (BMO) and synthetic galacto oligosaccharides (GOS) using mono- and cocultures of eight major bacteria related to a healthy infant microbiome. The results revealed that BMO treatments supported growth of Bifidobacterium longum subsp. longum and Parabacteroides distasonis, while at the same time growth of Clostridium perfringens and Escherichia coli was inhibited. In addition, there was a synergistic effect of combining lactose and BMO in regards to reducing C. perfringens, maintaining stable numbers of P. distasonis and simultaneously increasing numbers of the beneficial B. longum subsp. longum. These results indicate that the oligosaccharide composition plays a vital role in shaping the developing microbiota.

Inulin Ameliorates Alcoholic Liver Disease via Suppressing LPS-TLR4-Mψ Axis and Modulating Gut Microbiota in Mice.

BACKGROUND: Alcoholic liver disease (ALD) represents a chronic liver disorder caused by alcohol abuse. Numerous studies have demonstrated that gut microbiota dysbiosis plays a critical role in ALD pathogenesis. Application of prebiotic, probiotic, and dietary supplementation to the modulation of gut microbiota contributes to a novel approach to the management of ALD. Inulin, a natural prebiotic found in plants, can restore gut dysbiosis in ALD. However, the exact mechanism of dietary inulin in ALD remains largely unknown. METHODS: Sixty female C57BL/6J mice were randomly divided into 4 groups: pair-fed (PF) group (PF/CON); alcohol-fed (AF) group (AF/CON); PF with inulin (INU) group (PF/INU); and AF with INU group (AF/INU). All mice were fed with isocaloric modified Lieber-DeCarli liquid diets with or without alcohol. RESULTS: After 6 weeks of feeding, mice were euthanized and associated indications were investigated. The results showed that chronic ethanol (EtOH) intake led to the loss of body weights, abnormal levels of transaminases, and inflammatory indicators (lipopolysaccharide [LPS], interleukin [IL]-6, IL-10, tumor necrosis factor-α, IL-17A), while inulin administration ameliorated these effects. To further understand the underlying mechanism, we investigated macrophages (Mψs) and gut microbiota in diverse groups. The number of Mψs was reduced after dietary inulin treatment in chronic EtOH exposure. Hepatic Toll-like receptor 4 (TLR4+ ) Mψs in AF/INU group were lower than AF/CON group. 16S rRNA sequencing and analysis of gut microbiota indicated the reduction of Allobaculum, Lactobacillus, and Lactococcus, as well as the increase of Parasutterella in AF group compared with PF control. Increased Allobaculum, Lactobacillus, and Lactococcus but reduced Parasutterella in AF/INU group were confirmed that dietary inulin rectified gut dysbiosis to attenuate ALD. CONCLUSIONS: Dietary inulin ameliorates ALD via suppressing LPS-TLR4-Mψ axis and modulating gut microbiota in mice, thus potentially provides theoretical foundation for inulin intervention in the prevention and treatment of ALD.

Probiotics to prevent infantile colic.

BACKGROUND: Infantile colic is typically defined as full-force crying for at least three hours per day, on at least three days per week, for at least three weeks. Infantile colic affects a large number of infants and their families worldwide. Its symptoms are broad and general, and while not indicative of disease, may represent a serious underlying condition in a small percentage of infants who may need a medical assessment. Probiotics are live microorganisms that alter the microflora of the host and provide beneficial health effects. The most common probiotics used are of Lactobacillus, Bifidobacterium and Streptococcus. There is growing evidence to suggest that intestinal flora in colicky infants differ from those in healthy infants, and it is suggested that probiotics can redress this balance and provide a healthier intestinal microbiota landscape. The low cost and easy availability of probiotics makes them a potential prophylactic solution to reduce the incidence and prevalence of infantile colic. OBJECTIVES: To evaluate the efficacy and safety of prophylactic probiotics in preventing or reducing severity of infantile colic. SEARCH METHODS: In January 2018 we searched CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, 10 other databases and two trials registers. In addition, we handsearched the abstracts of relevant meetings, searched reference lists, ran citation searches of included studies, and contacted authors and experts in the field, including the manufacturers of probiotics, to identify unpublished trials. SELECTION CRITERIA: Randomised control trials (RCTs) of newborn infants less than one month of age without the diagnosis of infantile colic at recruitment. We included any probiotic, alone or in combination with a prebiotic (also known as synbiotics), versus no intervention, another intervention(s) or placebo, where the focus of the study was the effect of the intervention on infantile colic. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures of Cochrane. MAIN RESULTS: Our search yielded 3284 records, and of these, we selected 21 reports for full-text review. Six studies with 1886 participants met our inclusion criteria, comparing probiotics with placebo. Two studies examined Lactobacillus reuteri DSM, two examined multi-strain probiotics, one examined Lactobacillus rhamnosus, and one examined Lactobacillus paracasei and Bifidobacterium animalis. Two studies began probiotics during pregnancy and continued administering them to the baby after birth.We considered the risk of bias for randomisation as low for all six trials; for allocation concealment as low in two studies and unclear in four others. All studies were blinded, and at low risk of attrition and reporting bias.A random-effects meta-analysis of three studies (1148 participants) found no difference between the groups in relation to occurrence of new cases of colic: risk ratio (RR) 0.46, 95% confidence interval (CI) 0.18 to 1.19; low-certainty evidence; I2 = 72%.A random-effects meta-analysis of all six studies (1851 participants) found no difference between the groups in relation to serious adverse effects (RR 1.02, 95% CI 0.14 to 7.21; low-certainty evidence; I2 not calculable (only four serious events for one comparison, two in each group: meconium plug obstruction, patent ductus arteriosus and neonatal hepatitis).A random-effects meta-analysis of three studies (707 participants) found a mean difference (MD) of -32.57 minutes per day (95% CI -55.60 to -9.54; low-certainty evidence; I2 = 93%) in crying time at study end in favour of probiotics.A subgroup analysis of the most studied agent, Lactobacillus reuteri, showed a reduction of 44.26 minutes in daily crying with a random-effects model (95% CI -66.6 to -21.9; I2 = 92%), in favour of probiotics. AUTHORS' CONCLUSIONS: There is no clear evidence that probiotics are more effective than placebo at preventing infantile colic; however, daily crying time appeared to reduce with probiotic use compared to placebo. There were no clear differences in adverse effects.We are limited in our ability to draw conclusions by the certainty of the evidence, which we assessed as being low across all three outcomes, meaning that we are not confident that these results would not change with the addition of further research.

Arabinoxylan from Argentinian whole wheat flour promote the growth of Lactobacillus reuteri and Bifidobacterium breve.

Arabinoxylans are part of dietary fibre and have received attention given their emergent prebiotic character. Four arabinoxylans extracts were obtained from Argentinian soft and hard wheat. In vitro assays were performed to describe the extent to which the extracts from whole wheat flour support selective growth of Bifidobacterium breve and probiotic Lactobacillus reuteri ATCC23272 in a defined media. The prebiotic effect was evaluated by three quantitative scores: relative growth, prebiotic activity score and prebiotic index. For prebiotic index equation the growth of Bacteroides and Clostridium strains was compared to that of bifidobacteria and lactic acid bacteria. All the arabinoxylans extracts supported the growth of Lactobacillus and Bifidobacterium, reaching higher prebiotic activity score values than inulin (0·37 and 0·36 for Lactobacillus and Bifidobacterium respectively). AX2 from soft wheat and AX4 from hard showed similar prebiotic index value to commercial inulin (2·64, 2·52 and 2·22 respectively), and AX3 extract presented higher prebiotic index value (4·09) than the positive control and other prebiotic index reported for arabinoxylans. These extracts could be used as prebiotic, synbiotic compositions or novel food prototypes to treat dysbiosis associated with many diseases. SIGNIFICANCE AND IMPACT OF THE STUDY: The present work demonstrates that AX extracts from Argentinian soft and hard wheat promote efficiently the growth of probiotic strain L. reuteri ATCC23272 and B. breve 286, validated with three different parameters that consider the growth of representative strains of Bacteria genera found in the gut. The evaluation of AX extracts as a food supplement in a murine model could confirm their ability to modulate the microbiome. Novel food prototypes including AX and probiotics could relieve local symptoms and may act as psychobiotics with a beneficial effect on microbiome-brain axis.

Prebiotics as excipients for enhancement of stability and functionality of Bifidobacterium longum ssp. infantis with potential application as symbiotics in food and pharmaceuticals.

Objective: Formulations containing probiotics are promoted due to health benefits. During lyophilization and subsequent storage in the gastrointestinal tract, bacteria are exposed to stress conditions that can lead to impairment and loss of viability. Methods: The suitability of various excipients for enhancing the stability and functionality of Bifidobacterium longum subsp. infantis during storage as freeze-dried powder and through exposure to acid and bile was investigated. Cells were lyophilized in the presence of sucrose, trehalose, lactose, cellobiose and fructooligosaccharide (FOS) and stored at 4 °C or 25 °C. The effect of diverse protectants on the persistence after exposure to acid and bile environment was examined through determination of the colony forming units, the ß-glucosidase and ß-galactosidase activity and the membrane integrity changes. Results: Cells freeze-dried in the presence of cryoprotectants had comparable survivability during storage at 4 °C whereas the survival rate at 25 °C of cells protected by cellobiose and FOS was higher than for those protected with sucrose and trehalose. Furthermore, the respective excipients used as cryoprotectants enhanced the stability of cells exposed to simulated gastric and small intestinal medium. Stabilization may be achieved through different mechanism of action such as protecting the membrane integrity and as metabolizable substrates. Overall, prebiotic and thus metabolizable protectants including cellobiose and FOS were superior to other protectants used. Conclusion: In symbiotic formulas with B. infantis, these sugars might serve as prebiotics and stabilizers of this probiotic strain during lyophilization, storage and in gastrointestinal conditions simultaneously, potentially increasing its health-promoting effects.

Probiotics are a good choice in remission of inflammatory bowel diseases: A meta analysis and systematic review.

Altered gut bacteria and bacterial metabolic pathways are two important factors in initiation and progression of inflammatory bowel disease (IBD). However, efficacy of probiotics in remission of patients with IBD has not been characterized. This study was performed on the studies that specifically assessed the efficacy of probiotics in attaining clinical response on patients with various types of IBD. The efficacy of variant species of probiotics in different conditions and the influence of study quality in outcomes of randomized controlled trials (RCTs) were also assessed. The RCTs were collected by searching in MEDLINE Web of Science and Google scholar. Then all studies were abstracted in abstraction form and the outcomes were analyzed with fixed-effect and mixed-effect models for assessment of efficacy of variant species of probiotics in subgroups of IBDs. Analysis of 9 trials showed that probiotics had not significant effect on Crohn's disease (CD) (p = 0.07) but analysis of 3 trials in children with IBD revealed a significant advantage (p < 0.01). Analysis of 18 trials revealed that probiotics in patients with Ulcerative colitis (UC) in different conditions have significant effects (p = 0.007). VSL#3 probiotics in patients with UC had significant effect (p < 0.01). Combination of Lactobacillus probiotic, prebiotics had significant effect (p = 0.03) only in patients with UC. Combination of Saccharomyces boulardii, Lactobacillus, and VSL#3 probiotics in CD had also a trend for efficiency (p = 0.057). In children with IBD, the combination of Lactobacillus with VSL#3 probiotics had significant effect (p < 0.01). Probiotics are beneficial in IBD, especially the combination ones in UC.

Prebiotics, Bone and Mineral Metabolism.

Increasing interest in functional foods has driven discovery in the area of bioactive compounds. Prebiotics are non-digestible carbohydrate compounds that, when consumed, elicit health benefits and aid in the prevention and treatment of chronic diseases. While prebiotics have been shown to improve a number of chronic, inflammatory conditions, growing evidence exists for prebiotic effects on calcium metabolism and bone health. These novel dietary fibers have been shown to increase calcium absorption in the lower intestines of both preclinical and human models. Rodent models have also been imperative for understanding prebiotic effects on bone mineral density and measures of skeletal strength. Although fewer data are available for humans, bone-related prebiotic effects exist across the lifecycle, suggesting benefits for attainment of peak bone mass during adolescence and minimized bone resorption among postmenopausal women. These effects are thought to occur through prebiotic-microbe interactions in the large intestine. Current prebiotic mechanisms for improved mineral absorption and skeletal health include alterations in gut microbiota composition, production of short-chain fatty acids, altered intestinal pH, biomarker modification, and immune system regulation. While the majority of available data support improved mineral bioavailability, emerging evidence suggests alternate microbial roles and the presence of an intricate gut-bone signaling axis. Overall, the current scientific literature supports prebiotic consumption as a cost-effective and sustainable approach for improved skeletal health and/or fracture prevention. The goal of this review is to discuss both foundational and recent research in the area of prebiotics, mineral metabolism, and bone health.

Endo-xylanases as tools for production of substituted xylooligosaccharides with prebiotic properties.

Xylan has a main chain consisting of ß-1,4-linked xylose residues with diverse substituents. Endoxylanases cleave the xylan chain at cleavage sites determined by the substitution pattern and thus give different oligosaccharide product patterns. Most known endoxylanases belong to glycoside hydrolase (GH) families 10 and 11. These enzymes work well on unsubstituted xylan but accept substituents in certain subsites. The GH11 enzymes are more restricted by substituents, but on the other hand, they are normally more active than the GH10 enzymes on insoluble substrates, because of their smaller size. GH5 endoxylanases accept arabinose substituents in several subsites and require it in the - 1 subsite. This specificity makes the GH5 endoxylanases very useful for degradation of highly arabinose-substituted xylans and for the selective production of arabinoxylooligosaccharides, without formation of unsubstituted xylooligosaccharides. The GH30 endoxylanases have a related type of specificity in that they require a uronic acid substituent in the - 2 subsite, which makes them very useful for the production of uronic acid substituted oligosaccharides. The ability of dietary xylooligosaccharides to function as prebiotics in humans is governed by their substitution patterns. Endoxylanases are thus excellent tools to tailor prebiotic oligosaccharides to stimulate various types of intestinal bacteria and to cause fermentation in different parts of the gastrointestinal tract. Continuously increasing knowledge on the function of the gut microbiota and discoveries of novel endoxylanases increase the possibilities to achieve health-promoting effects.