Significance of Inulin Fructans in the Human Diet

Impacts of Whole-Grain Soft Red, Whole-Grain Soft White, and Refined Soft White Wheat Flour Crackers on Gastrointestinal Inflammation and the Gut Microbiota of Adult Humans

Consumption of whole-grain wheat has been associated with positive health outcomes, but it remains unclear whether different types of wheat elicit varying effects on the gut microbiome and intestinal inflammation. The objectives of this research were to investigate the effect of two whole-grain wheat flours versus refined wheat flour on the diversity of the human gut microbiota, as well as on butyrate production capacity and gastrointestinal inflammation, using one-week dietary interventions. For this study, 28 participants were recruited, with ages ranging from 18 to 55 years and a mean BMI of 26.0 kg/m2. For four weeks, participants were provided 80 g daily servings of different wheat crackers: Week A was a run-in period of crackers made from soft white wheat flour, Week B crackers were whole-grain soft white wheat flour, Week C crackers were a wash-out period identical to Week A, and Week D crackers were whole-grain soft red wheat flour. At the end of each week, participants provided fecal samples that were analyzed for markers of intestinal inflammation, including lipocalin and calprotectin, using enzyme-linked immunosorbent assays and quantitative real-time PCR. The primary outcome, gut bacterial community alpha and beta diversity, was similar across timepoints. Three taxa significantly differed in abundance following both whole-grain wheat flour interventions: Escherichia/Shigella and Acidaminococcus were significantly depleted, and Lachnospiraceae NK4A136 group was enriched. Secondary outcomes determined that protein markers of intestinal inflammation and genes related to putative butyrate production capacity were similar throughout the study period, with no significant changes. Lipocalin concentrations ranged from 14.8 to 22.6 ng/mL while calprotectin ranged from 33.2 to 62.5 ng/mL across all 4 weeks. The addition of wheat crackers to the adult human subjects' usual diet had a minimal impact on their gastrointestinal inflammation or the gut microbiota.

Agave-Laurate-Bioconjugated Fructans Decrease Hyperinsulinemia and Insulin Resistance, Whilst Increasing IL-10 in Rats with Metabolic Syndrome Induced by a High-Fat Diet

Metabolic syndrome (MetS) comprises a cluster of metabolic risk factors, which include obesity, hypertriglyceridemia, high blood pressure, and insulin resistance. The purpose of this study was to evaluate the effects of laurate-bioconjugated fructans on pro- and anti-inflammatory cytokines in Wistar rats with MetS induced by a high-fat diet. Laurate-bioconjugated fructans were synthesized with agave fructans, immobilized lipase B, and vinyl laureate as the acylant. Groups were fed a standard diet (NORMAL), a high-fat diet (HFD), or a high-fat diet plus laurate-bioconjugated fructans (FL PREV) for 9 weeks. A fourth group received a high-fat diet for 6 weeks, followed by simultaneous exposure to a high-fat diet and laurate-bioconjugated fructans for 3 additional weeks (FL REV). The dose of laurate-bioconjugated fructans was 130 mg/kg. Laurate-bioconjugated fructans reduced food and energy intake, body weight, body mass index, abdominal circumference, adipose tissue, adipocyte area, serum triglycerides, insulin, insulin resistance, and C-reactive protein but they increased IL-10 protein serum levels and mRNA expression. The impact of laurate-bioconjugated fructans on zoometric and metabolic parameters supports their potential as therapeutic agents to improve obesity, obesity comorbidities, insulin resistance, type 2 diabetes mellitus, and MetS.

Dietary patterns interfere with gut microbiota to combat obesity

Obesity and obesity-related metabolic disorders are global epidemics that occur when there is chronic energy intake exceeding energy expenditure. Growing evidence suggests that healthy dietary patterns not only decrease the risk of obesity but also influence the composition and function of the gut microbiota. Numerous studies manifest that the development of obesity is associated with gut microbiota. One promising supplementation strategy is modulating gut microbiota composition by dietary patterns to combat obesity. In this review, we discuss the changes of gut microbiota in obesity and obesity-related metabolic disorders, with a particular emphasis on the impact of dietary components on gut microbiota and how common food patterns can intervene in gut microbiota to prevent obesity. While there is promise in intervening with the gut microbiota to combat obesity through the regulation of dietary patterns, numerous key questions remain unanswered. In this review, we critically review the associations between dietary patterns, gut microbes, and obesity, aiming to contribute to the further development and application of dietary patterns against obesity in humans.

Prebiotic inulin ameliorates SARS-CoV-2 infection in hamsters by modulating the gut microbiome

Current treatment options for COVID-19 are limited, with many antivirals and immunomodulators restricted to the most severe cases and preventative care limited to vaccination. As the SARS-CoV-2 virus and its increasing variants threaten to become a permanent fixture of our lives, this new reality necessitates the development of cost-effective and accessible treatment options for COVID-19. Studies have shown that there are correlations between the gut microbiome and severity of COVID-19, especially with regards to production of physiologically beneficial short-chain fatty acids (SCFAs) by gut microbes. In this study, we used a Syrian hamster model to study how dietary consumption of the prebiotic inulin affected morbidity and mortality resulting from SARS-CoV-2 infection. After two weeks of observation, we discovered that inulin supplementation attenuated morbid weight loss and increased survival rate in hamster subjects. An analysis of microbiome community structure showed significant alterations in 15 genera. Notably, there were also small increases in fecal DCA and a significant increase in serum DCA, perhaps highlighting a role for this secondary bile acid in conferring protection against SARS-CoV-2. In light of these results, inulin and other prebiotics are promising targets for future investigation as preventative treatment options for COVID-19.

Identification of inulin-responsive bacteria in the gut microbiota via multi-modal activity-based sorting

Prebiotics are defined as non-digestible dietary components that promote the growth of beneficial gut microorganisms. In many cases, however, this capability is not systematically evaluated. Here, we develop a methodology for determining prebiotic-responsive bacteria using the popular dietary supplement inulin. We first identify microbes with a capacity to bind inulin using mesoporous silica nanoparticles functionalized with inulin. 16S rRNA gene amplicon sequencing of sorted cells revealed that the ability to bind inulin was widespread in the microbiota. We further evaluate which taxa are metabolically stimulated by inulin and find that diverse taxa from the phyla Firmicutes and Actinobacteria respond to inulin, and several isolates of these taxa can degrade inulin. Incubation with another prebiotic, xylooligosaccharides (XOS), in contrast, shows a more robust bifidogenic effect. Interestingly, the Coriobacteriia Eggerthella lenta and Gordonibacter urolithinfaciens are indirectly stimulated by the inulin degradation process, expanding our knowledge of inulin-responsive bacteria.

Plant fructans: Recent advances in metabolism, evolution aspects and applications for human health

Fructans, fructose polymers, are one of the three major reserve carbohydrate in plants. The nutritional and therapeutic benefits of natural fructans in plants have attracted increasing interest by consumers and food industry. In the course of evolution, many plants have developed the ability of regulating plant fructans metabolism to produce fructans with different structures and chain lengths, which are strongly correlated with their survival in harsh environments. Exploring these evolution-related genes in fructans biosynthesis and de novo domestication of fructans-rich plants based on genome editing is a viable and promising approach to improve human dietary quality and reduce the risk of chronic disease. These advances will greatly facilitate breeding and production of tailor-made fructans as a healthy food ingredient from wild plants such as huangjing (Polygonatum cyrtonema). The purpose of this review is to broaden our knowledge on plant fructans biosynthesis, evolution and benefits to human health.

Associating Inulin with a Pea Protein Improves Fast-Twitch Skeletal Muscle Mass and Muscle Mitochondrial Activities in Old Rats

Aging is associated with a decline in muscle mass and function, leading to increased risk for mobility limitations and frailty. Dietary interventions incorporating specific nutrients, such as pea proteins or inulin, have shown promise in attenuating age-related muscle loss. This study aimed to investigate the effect of pea proteins given with inulin on skeletal muscle in old rats. Old male rats (20 months old) were randomly assigned to one of two diet groups for 16 weeks: a 'PEA' group receiving a pea-protein-based diet, or a 'PEA + INU' group receiving the same pea protein-based diet supplemented with inulin. Both groups showed significant postprandial stimulation of muscle p70 S6 kinase phosphorylation rate after consumption of pea proteins. However, the PEA + INU rats showed significant preservation of muscle mass with time together with decreased MuRF1 transcript levels. In addition, inulin specifically increased PGC1-α expression and key mitochondrial enzyme activities in the plantaris muscle of the old rats. These findings suggest that dietary supplementation with pea proteins in combination with inulin has the potential to attenuate age-related muscle loss. Further research is warranted to explore the underlying mechanisms and determine the optimal dosage and duration of intervention for potential translation to human studies.

Marine Chitosan-Oligosaccharide Ameliorated Plasma Cholesterol in Hypercholesterolemic Hamsters by Modifying the Gut Microflora, Bile Acids, and Short-Chain Fatty Acids

This study evaluated the cholesterol-alleviating effect and underlying mechanisms of chitosan-oligosaccharide (COS) in hypercholesterolemic hamsters. Male hamsters (n = 24) were divided into three groups in a random fashion, and each group was fed one particular diet, namely a non-cholesterol diet (NCD), a high-cholesterol diet (HCD), and an HCD diet substituting 5% of the COS diet for six weeks. Subsequently, alterations in fecal bile acids (BAs), short-chain fatty acids (SCFAs), and gut microflora (GM) were investigated. COS intervention significantly reduced and increased the plasma total cholesterol (TC) and high-density lipoprotein-cholesterol (HDL-C) levels in hypercholesteremic hamsters. Furthermore, Non-HDL-C and total triacylglycerols (TG) levels were also reduced by COS supplementation. Additionally, COS could reduce and increase food intake and fecal SCFAs (acetate), respectively. Moreover, COS had beneficial effects on levels of BAs and GM related to cholesterol metabolism. This study provides novel evidence for the cholesterol-lowering activity of COS.

Supplementation with inulin-type fructans affects gut microbiota and attenuates some of the cardiometabolic benefits of a plant-based diet in individuals with overweight or obesity

Background

The gut microbiota has emerged as a potential therapeutic target to improve the management of obesity and its comorbidities.

Objective

We investigated the impact of a high fiber (∼38 g/d) plant-based diet, consumed ad libitum, with or without added inulin-type fructans (ITF), on the gut microbiota composition and cardiometabolic outcomes in subjects with obesity. We also tested if baseline Prevotella/Bacteroides (P/B) ratio predicts weight loss outcomes.

Methods

This is a secondary exploratory analysis from the PREVENTOMICS study, in which 100 subjects (82 completers) aged 18-65 years with body mass index 27-40 kg/m2 were randomized to 10 weeks of double-blinded treatment with a personalized or a generic plant-based diet. Changes from baseline to end-of-trial in gut microbiota composition (16S rRNA gene amplicon sequencing), body composition, cardiometabolic health and inflammatory markers were evaluated in the whole cohort (n = 82), and also compared in the subgroup of subjects who were supplemented with an additional 20 g/d ITF-prebiotics (n = 21) or their controls (n = 22).

Results

In response to the plant-based diet, all subjects lost weight (-3.2 [95% CI -3.9, -2.5] kg) and experienced significant improvements in body composition and cardiometabolic health indices. Addition of ITF to the plant-based diet reduced microbial diversity (Shannon index) and selectively increased Bifidobacterium and Faecalibacterium (q < 0.05). The change in the latter was significantly associated with higher values of insulin and HOMA-IR and lower HDL cholesterol. In addition, the LDL:HDL ratio and the concentrations of IL-10, MCP-1 and TNFα were significantly elevated in the ITF-subgroup. There was no relationship between baseline P/B ratio and changes in body weight (r = -0.07, p = 0.53).

Conclusion

A plant-based diet consumed ad libitum modestly decreases body weight and has multiple health benefits in individuals with obesity. Addition of ITF-prebiotics on top this naturally fiber-rich background selectively changes gut microbiota composition and attenuates some of the realized cardiometabolic benefits.

Clinical trial registration

[https://clinicaltrials.gov/ct2/show/NCT04590989], identifier [NCT04590989].

Inulin: properties and health benefits

Inulin, a soluble dietary fiber, is widely found in more than 36 000 plant species as a reserve polysaccharide. The primary sources of inulin, include Jerusalem artichoke, chicory, onion, garlic, barley, and dahlia, among which Jerusalem artichoke tubers and chicory roots are often used as raw materials for inulin production in the food industry. It is universally acknowledged that inulin as a prebiotic has an outstanding effect on the regulation of intestinal microbiota via stimulating the growth of beneficial bacteria. In addition, inulin also exhibits excellent health benefits in regulating lipid metabolism, weight loss, lowering blood sugar, inhibiting the expression of inflammatory factors, reducing the risk of colon cancer, enhancing mineral absorption, improving constipation, and relieving depression. In this review paper, we attempt to present an exhaustive overview of the function and health benefits of inulin.

A major mechanism for immunomodulation: Dietary fibres and acid metabolites

Diet and the gut microbiota have a profound influence on physiology and health, however, mechanisms are still emerging. Here we outline several pathways that gut microbiota products, particularly short-chain fatty acids (SCFAs), use to maintain gut and immune homeostasis. Dietary fibre is fermented by the gut microbiota in the colon, and large quantities of SCFAs such as acetate, propionate, and butyrate are produced. Dietary fibre and SCFAs enhance epithelial integrity and thereby limit systemic endotoxemia. Moreover, SCFAs inhibit histone deacetylases (HDAC), and thereby affect gene transcription. SCFAs also bind to 'metabolite-sensing' G-protein coupled receptors (GPCRs) such as GPR43, which promotes immune homeostasis. The enormous amounts of SCFAs produced in the colon are sufficient to lower pH, which affects the function of proton sensors such as GPR65 expressed on the gut epithelium and immune cells. GPR65 is an anti-inflammatory Gα_s-coupled receptor, which leads to the inhibition of inflammatory cytokines. The importance of GPR65 in inflammatory diseases is underscored by genetics associated with the missense variant I231L (rs3742704), which is associated with human inflammatory bowel disease, atopic dermatitis, and asthma. There is enormous scope to manipulate these pathways using specialized diets that release very high amounts of specific SCFAs in the gut, and we believe that therapies that rely on chemically modified foods is a promising approach. Such an approach includes high SCFA-producing diets, which we have shown to decrease numerous inflammatory western diseases in mouse models. These diets operate at many levels - increased gut integrity, changes to the gut microbiome, and promotion of immune homeostasis, which represents a new and highly promising way to prevent or treat human disease.

Exploring the influence of ultrasound on the antibacterial emulsification stability of lysozyme-oregano essential oil

A lysozyme-oregano essential oil (Lys-OEO) antibacterial emulsion was developed via ultrasonic treatment. Based on the general emulsion materials of ovalbumin (OVA) and inulin (IN), the addition of Lys and OEO successfully inhibited the growth of E. coli and S. aureus, two representatives of which were Gram-negative and Gram-positive bacteria respectively. The emulsion system in this study was designed to compensate for the limitation that Lys could only act on Gram-positive bacteria, and the stability of the emulsion was improved using ultrasonic treatment. The optimal amounts among OVA, Lys and OEO were found to be the mass ratio of 1:1 (Lys to OVA) and 20% (w/w) OEO. The ultrasonic treatment at the power of 200, 400, 600, and 800 W and time length of 10 min improved the stability of emulsion, in which the surface tension was below 6.04 mN/m and the Turbiscan stability index (TSI) did not exceed 10. The multiple light scattering showed that sonicated emulsions were less prone to delamination; salt stability and pH stability of emulsions were improved, CLSM image showed emulsion as oil-in-water type. In the meantime, the particles of the emulsions were found to become smaller and more uniform with ultrasonic treatment. The best dispersion and stability of the emulsion were both achieved at 600 W with a zeta potential of 7.7 mV, the smallest particle size and the most uniform particle distribution.

Effects of inulin on calcium metabolism and bone health

Inulin, a dietary fibre found in the roots of many plants, has positive effects on health. It is particularly noteworthy due to its positive impact on calcium metabolism. Inulin has significant functions, such as improving calcium absorption through passive diffusion, bolstering calcium absorption via ion exchange and expanding the absorption surface of the colon by stimulating cell growth. In addition, inulin boosts calcium absorption by increasing calcium solubility, stimulating levels of calcium-binding protein expression and increasing useful microorganisms. It increases calbindin levels and stimulates transcellular active calcium transport. An inulin intake of least 8-10 g/day supports calcium absorption and total body bone mineral content/density in adolescents through its known mechanisms of action. It also significantly enhances calcium absorption and improves bone health in postmenopausal women and adult men. Sustained and sufficient inulin supplementation in adults has a positive effect on calcium metabolism and bone mineral density.

Influence of biotic interventions on the immune response to vaccines in young and older adults

Vaccination is the most effective way to confer potent and long-term protection from infectious diseases. However, poorer responses to immunization are common in young adults with sub-optimal immune health and the elderly because of immunosenescence and increased comorbidities. Recent mechanistic studies have highlighted that the microbiota and its compounds modulate many molecular pathways that can influence the host immune system. Consequently, altering the microbiota composition or activity with immunonutrition, specifically with biotic interventions (probiotics, prebiotics, synbiotics, or postbiotics), may enhance the immune response and vaccine efficacy. This review aims to examine the available data for these biotic strategies to provide clinicians, researchers, and vaccine developers with a mechanistically driven synthesis of how biotic interventions could modulate the immune responses to vaccination. The article describes some postulated mechanistic pathways involved in immunological responses to vaccines and immunomodulation with biotic interventions. Randomized clinical trials were also reviewed to evaluate the impact of specific biotic interventions on vaccination outcomes in different age groups. Few strains and formulations significantly increased antigen-specific antibody titers in individual of all ages. However, studies have also pointed to a substantial heterogeneity that can be attributed to the difference in biotic intervention, strain, dose, viability, type of vaccine antigen, study location, as well as duration, and timing of administration. Future investigations should focus on establishing optimal strains, doses, and timing of administration with respect to vaccination, especially in the elderly and children, where vaccine effectiveness and duration of immunization matter.

Preparation of an LZ-OEO Compound Antibacterial Gel and the Effect of Microwave Treatment on Its Structure and Stability

Composite gels prepared with ovalbumin (OVA) as basic materials have been gradually utilized in food and biological fields. However, the structure and function of gels made from natural materials are not perfect, especially the hardness, viscoelasticity and water-holding capacity of gels, which are easily affected by various factors (pH, NaCl, etc.). In order to improve the antibacterial effect and safety of gels, and on the basis of exploring the bacteriostatic formula of lysozyme-oregano essential oil (LZ-OEO), the influence of microwave treatment on the stability of the composite bacteriostatic material gel was emphatically investigated and discussed so as to develop a new bacteriostatic gel material. The results revealed that the LZ-OEO antibacterial gel prepared by adding 20% OEO, with a ratio of 3:2 between OVA and LZ, was more stable after microwave treatment, and the synergistic antibacterial effect was significantly improved. That is, the OVA and LZ-OEO composite gel processed using a 350 W microwave treatment for 1 min had the highest hardness, the water-holding capacity reached 78.05% and a dense and ordered network structure was formed. In addition, the compound gel displayed excellent antibacterial effects against Staphylococcus aureus and Escherichia coli. The experimental findings in this study effectively expands the application scope of lysozyme antibacterial materials and provides a more favorable technical foundation for future development and utilization.

Effect and mechanism of functional compound fruit drink on gut microbiota in constipation mice

Compound fruit drink (CFD) is a functional drink prepared with fruit, Chinese herbs and prebiotic fructooligosaccharide as the main ingredients. Loperamide hydrochloride was used to establish a mouse model of constipation. And the effect of CFD on the improvement of constipation and the impact on gut microbiota were studied. The results showed that CFD significantly enhanced intestinal motility in constipated mice (P < 0.05). It significantly improved serum levels of gastrointestinal regulatory-related peptides, elevated the short-chain fatty acids (SCFAs) content and alleviated colonic injury. Meanwhile, CFD also up-regulated the mRNA expression levels of AQP3, AQP9, SCF and c-Kit and the related protein expression levels. Fecal microbial results showed that the CFD medium-dose group significantly increased species richness. Furthermore, CFD increased the abundance of potentially beneficial bacteria and reduced the number of potentially pathogenic bacteria. This study indicated that CFD was a promising functional drink for effectively relieving constipation.

The potential of dandelion in the fight against gastrointestinal diseases: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Dandelion (Taraxacum officinale Weber ex F. H. Wigg.), as a garden weed grown globally, has long been consumed as a therapeutic herb. Its folkloric uses include treatments of digestive disorders (dyspepsia, anorexia, stomach disorders, gastritis and enteritis) and associate complex ailments involving uterine, liver and lung disorders.

AIM OF THE STUDY

The present study aims to critically assess the current state of research and summarize the potential roles of dandelion and its constituents in gastrointestinal (GI) -protective actions. A focus is placed on the reported bioactive components, pharmacological activities and modes of action (including molecular mechanisms and interactions among bioactive substances) of dandelion products/preparations and derived active constituents related to GI protection.

MATERIALS AND METHODS

The available information published prior to August 2021 was reviewed via SciFinder, Web of Science, Google Scholar, PubMed, Elsevier, Wiley On-line Library, and The Plant List. The search was based on the ethnomedical remedies, pharmacological activities, bioactive compounds of dandelion for GI protection, as well as the interactions of the components in dandelion with the gut microbiota or biological regulators, and with other ingested bioactive compounds. The key search words were "Taraxacum" and "dandelion".

RESULTS

T. coreanum Nakai, T. mongolicum and T. officinale are the most commonly used species for folkloric uses, with the whole plant, leaves and root of dandelion being used more frequently. GI-protective substances of dandelion include taraxasterol, taraxerol, caffeic acid, chicoric acid, chlorogenic acid, luteolin and its glucosides, polysaccharides, inulin, and β-sitosterol. Dandelion products and derived constituents exhibit pharmacological effects against GI disorders, mainly including dyspepsia, gastroesophageal reflux disease, gastritis, small intestinal ulcer, ulcerative colitis, liver diseases, gallstones, acute pancreatitis, and GI malignancy. The underlying molecular mechanisms may include immuno-inflammatory mechanisms, apoptosis mechanism, autophagy mechanism, and cholinergic mechanism, although interactions of dandelion's constituents with GI health-related biological entities (e.g., GI microbiota and associated biological modulators) or other ingested bioactive compounds shouldn't be ignored.

CONCLUSION

The review reveals some in vivo and in vitro studies on the potential of dandelion derived products as complementary and alternative medicines/therapeutics against GI disorders. The whole herb may alleviate some symptoms related GI immuno-inflammatory basing on the abundant anti-inflammatory and anti-oxide active substances. Dandelion root could be a nontoxic and effective anticancer alternative, owing to its abundant terpenoids and polysaccharides. However, research related to GI protective dandelion-derived products remains limited. Besides the need of identifying bioactive compounds/complexes in various dandelion species, more clinical studies are also required on the metabolism, bioavailability and safety of these substances to support their applications in food, medicine and pharmaceuticals.

Global, distinctive, and personal changes in molecular and microbial profiles by specific fibers in humans

Dietary fibers act through the microbiome to improve cardiovascular health and prevent metabolic disorders and cancer. To understand the health benefits of dietary fiber supplementation, we investigated two popular purified fibers, arabinoxylan (AX) and long-chain inulin (LCI), and a mixture of five fibers. We present multiomic signatures of metabolomics, lipidomics, proteomics, metagenomics, a cytokine panel, and clinical measurements on healthy and insulin-resistant participants. Each fiber is associated with fiber-dependent biochemical and microbial responses. AX consumption associates with a significant reduction in LDL and an increase in bile acids, contributing to its observed cholesterol reduction. LCI is associated with an increase in Bifidobacterium. However, at the highest LCI dose, there is increased inflammation and elevation in the liver enzyme alanine aminotransferase. This study yields insights into the effects of fiber supplementation and the mechanisms behind fiber-induced cholesterol reduction, and it shows effects of individual, purified fibers on the microbiome.

Dietary Fiber as a Counterbalance to Age-Related Microglial Cell Dysfunction

With increasing age, microglia shift toward a pro-inflammatory phenotype that may predispose individuals to neurodegenerative disease. Because fiber fermentation in the colon produces bioactive short-chain fatty acids (SCFAs; e.g., acetate, butyrate, and propionate) that signal through the gut-brain axis, increasing dietary fiber may prevent or reverse age-related dysregulation of microglia. Adult (3–4 months old) and aged (23–24 months old) male and female mice were given ad libitum access to a modified AIN-93M diet with 1% cellulose or the same diet with 2.5 or 5.0% inulin for 8 weeks. Several adult and aged male mice fed 0 or 5% inulin were randomly selected for whole brain single-cell RNA sequencing (scRNA-seq) and differential gene expression analysis to classify brain microglia according to gene expression profile; and identify additional genetic markers of aging as possible targets for dietary interventions. Microglia were isolated from remaining mice and expression of selected aging-, inflammatory-, and sensome-related genes was assessed by Fluidigm as was the ex vivo secretion of tumor necrosis factor-alpha (TNF-α). SCFAs were measured in samples collected from the cecum. Microglia from adult and aged mice segregated into distinct phenotypes according to their gene expression profile. In aged mice, a considerably greater proportion of the population of microglia was identified being “activated” and a considerably smaller proportion was identified being “quiescent.” These findings using whole brain scRNA-seq were largely corroborated using highly purified microglia and Fluidigm analysis to assess a selected panel of genes. Aged mice compared to adults had lower levels of SCFA’s in cecum. Dietary inulin increased SCFAs in cecum and mostly restored microglial cell gene expression and TNF-α secretion to that seen in adults. Sex differences were observed with females having lower levels of SCFAs in cecum and increased neuroinflammation. Overall, these data support the use of fiber supplementation as a strategy to counterbalance the age-related microglial dysregulation.

Are all dietary fibers equal for patients with inflammatory bowel disease? A systematic review of randomized controlled trials

CONTEXT

Conflicting practice-based dietary recommendations are sometimes given to patients with inflammatory bowel disease (IBD); whereas intake of fiber should increase during remission, it should be avoided during relapse. Moreover, European countries set daily requirements of total fiber and do not specify any types.

OBJECTIVE

This systematic review appraised data from randomized clinical trials (RCTs) of the types of fibers beneficial for patients in the treatment of IBD to guide dietary fiber advice.

DATA SOURCES

The PubMED database was searched following PRISMA guidelines.

DATA EXTRACTION

RCTs evaluating the effects of any type of fiber on clinical and physiological outcomes in patients with IBD were assessed. Quality assessment of the selected full-text articles was conducted using the Cochrane Risk of Bias Tool.

DATA ANALYSIS

Eight studies were included reporting on 5 types of fibers. In 2 RCTs, germinated barley foodstuff (GBF) was shown to lower pro-inflammatory cytokines and clinical disease activity scores. Fructo-oligosaccharides (FOS) were demonstrated to lower IBD Questionnaire scores (lower well-being), in contrast to inulin, which decreased disease activity scores. An RCT could not find lower remission rates in the psyllium treatment group, while another RCT reported that administration led to less symptoms in patients. In RCTs, no concrete evidence was found that wheat bran improves disease course.

CONCLUSIONS

Although the evidence is sparse, GBF and inulin seem propitious and merit further exploration. Evidence on wheat bran and psyllium is still too limited. Adequately powered long-term human RCTs with objective outcomes are needed to improve dietary advice on types of fiber in IBD.

Fatty acids and beyond: Age and Alzheimer's disease related changes in lipids reveal the neuro-nutraceutical potential of lipids in cognition

Lipids are essential in maintaining brain function, and lipid profiles have been reported to be altered in aged and Alzheimer's disease (AD) brains as compared to healthy mature brains. Both age and AD share common metabolic hallmarks such as increased oxidative stress and perturbed metabolic function, and age remains the most strongly correlated risk factor for AD, a neurodegenerative disease. A major accompanying pathological symptom of these conditions is cognitive impairment, which is linked with changes in lipid metabolism. Thus, nutraceuticals that affect brain lipid metabolism or lipid levels as a whole have the potential to ameliorate cognitive decline. Lipid analyses and lipidomic studies reveal changes in specific lipid types with aging and AD, which can identify potential lipid-based nutraceuticals to restore the brain to a healthy lipid phenotype. The brain lipid profile can be influenced directly with dietary administration of lipids themselves, although because of synergistic effects of nutrients it may be more useful to consider a multi-component diet rather than single nutrient supplementation. Gut microbiota also serve as a source of beneficial lipids, and the value of treatments that manipulate the composition of gut microbiome should not be ignored. Lastly, instead of direct supplementation, compounds that affect pathways involved with lipid metabolism should also be considered as a way of manipulating lipid levels to improve cognition. In this review, we briefly discuss the role of lipids in the brain, the changing lipid profile in AD, current research on lipid-based nutraceuticals and their therapeutic potential to combat cognitive impairment.

Fermentation of Pleurotus ostreatus and Ganoderma lucidum mushrooms and their extracts by the gut microbiota of healthy and osteopenic women: potential prebiotic effect and impact of mushroom fermentation products on human osteoblasts

Recent data have highlighted the role of the gut microbiota and its several metabolites in maintaining bone health. Thus, gut microbiota manipulation, e.g., by prebiotics, might offer a plausible target in the fight against bone degenerative diseases. This study aimed (a) to investigate the in vitro prebiotic potential of Ganoderma lucidum and Pleurotus ostreatus mushrooms in healthy and osteopenic women and (b) to explore the impact of mushroom fermentation products on human osteoblasts. G. lucidum LGAM 9720 and P. ostreatus IK 1123 lyophilized mushroom-powders (2% w/v) and their hot-water extracts (1% w/v) were fermented in a 24 h static batch culture model by using faecal inocula from healthy (n = 3) or osteopenic (n = 3) donors. Gut microbiota analysis (qPCR) and measurement of short chain fatty acids (SCFAs) were performed during fermentation, and 24 h-prebiotic indexes were calculated. Evaluation of the effects of fermentation products on bone metabolism parameters (OPG: osteoprotegerin; and RANKL: receptor activator of nuclear factor kappa B ligand) in osteoblast cultures was also performed. Our data suggest that the origin of the gut microbiota inoculum plays a major role in the viability of osteoblasts. The treatments using P. ostreatus mushroom-powder and G. lucidum mushroom-extract had positive effects based on gut microbiota and SCFA analyses. Both mushrooms exhibited lower RANKL levels compared to controls, whereas their extracts tended to enhance the osteoblastic activity. In conclusion, mushrooms that are rich in beta-glucans may exert beneficial in vitro effects on bone physiology by alterations in the gut microbiota and/or SCFA production.

Development of Probiotic Almond Beverage Using Lacticaseibacillus rhamnosus GR-1 Fortified with Short-Chain and Long-Chain Inulin Fibre

Plant-based beverages are growing in popularity due to the rise of vegetarianism and other health trends. A probiotic almond beverage that combines the properties of almonds, inulin, and Lacticaseibacillusrhamnosus GR-1 may meet the demand for a non-dairy health-promoting food. The purpose of this study was to investigate the viability of L. rhamnosus GR-1 and pH in five fermented almond beverage samples, supplemented with either 2% or 5% (w/v) short-chain or long-chain inulin over 9 h of fermentation and 30 days of refrigerated storage. All almond beverage samples achieved a mean viable count of at least 107 CFU/mL during 9h of fermentation and 30 days of refrigerated storage. The probiotic almond beverage supplemented with 2% (w/v) short-chain inulin had a significantly higher mean microbial count (p = 0.048) and lower pH (p < 0.001) throughout fermentation, while the control and the long-chain inulin treatments had the lowest viable counts and acidity, respectively. This study shows that the addition of short-chain and long-chain inulin had no adverse effects on the viability of L. rhamnosus GR-1. Therefore, the probiotic almond beverage has the potential to be a valid alternative to dairy-based probiotic products.

Health benefits of whole grain: effects on dietary carbohydrate quality, the gut microbiome, and consequences of processing

Grains are important sources of carbohydrates in global dietary patterns. The majority of these carbohydrates, especially in refined-grain products, are digestible. Most carbohydrate digestion takes place in the small intestine where monosaccharides (predominantly glucose) are absorbed, delivering energy to the body. However, a considerable part of the carbohydrates, especially in whole grains, is indigestible dietary fibers. These impact gut motility and transit and are useful substrates for the gut microbiota affecting its composition and quality. For the most part, the profile of digestible and indigestible carbohydrates and their complexity determine the nutritional quality of carbohydrates. Whole grains are more complex than refined grains and are promoted as part of a healthy and sustainable diet mainly because the contribution of indigestible carbohydrates, and their co-passenger nutrients, is significantly higher. Higher consumption of whole grain is recommended because it is associated with lower incidence of, and mortality from, CVD, type 2 diabetes, and some cancers. This may be due in part to effects on the gut microbiota. Although processing of cereals during milling and food manufacturing is necessary to make them edible, it also offers the opportunity to still further improve the nutritional quality of whole-grain flours and foods made from them. Changing the composition and availability of grain carbohydrates and phytochemicals during processing may positively affect the gut microbiota and improve health.

Flexibility of Gut Microbiota in Ageing Individuals during Dietary Fiber Long-Chain Inulin Intake

SCOPE

During ageing, dysbiosis in the intestinal microbiota may occur and impact health. There is a paucity of studies on the effect of fiber on the elderly microbiota and the flexibility of the aged microbiota upon prebiotic intake. It is hypothesized that chicory long-chain inulin consumption can change microbiota composition, microbial fermentation products, and immunity in the elderly.

METHODS AND RESULTS

A double-blind, placebo-controlled trial is performed in healthy individuals (55-80 years), in which microbiota composition is studied before, during, and after two months of chicory long-chain inulin consumption. Fecal short chain fatty acid concentrations, T cell subsets, and antibody responses against a Hepatitis B (HB) vaccine are measured as well. Inulin consumption modified the microbiota composition, as measured by 16S rRNA sequencing. Participants consuming inulin have higher microbial diversity and a relatively higher abundance of the Bifidobacterium genus, as well as Alistipes shahii, Anaerostipes hadrus, and Parabacteroides distasonis. While the immune responses remain unchanged, the isobutyric acid levels, an undesired fermentation product, tend to be lower in the inulin group.

CONCLUSIONS

Overall, it is shown that the gut microbiota composition is still sensitive to chicory long-chain inulin induced changes in an ageing population, although this did not translate into an improved immune response to an HB vaccine.

Tostes M, Costa NM. The Potential Prebiotic Effects of Yacon (Smallanthus sonchifolius) in Colorectal Cancer

Background:

Colorectal cancer is caused by genetic predisposition and lifestyle risk factors and is associated with altered homeostasis of the intestinal microbiota. Evidence suggests that chronic infection and inflammation contribute to carcinogenic mutagenesis and promote cancer initiation and progression. Food components with prebiotic properties, such as fructooligosaccharides (FOS), promote intestinal integrity and health benefits. Yacon (Smallanthus sonchifolius) is an abundant source of FOS, which are fermented by beneficial bacteria, improving the intestinal environment affected by colorectal cancer.

Objective:

In the current review, the aim was to discuss colorectal cancer and its inflammatory process of development. Also, some general aspects concerning yacon roots and its prebiotic properties are described. Finely, the beneficial effects of yacon to reduce intestinal parameters altered due to colorectal cancer are summarized.

Conclusion:

It was verified that yacon might improve immunological parameters, intestinal barrier, intestinal microbiota, and inflammation in induced colorectal cancer in animals, especially. Researches with humans must be further investigated to prove these positive effects.

Influence of Prebiotic Activity of Agave salmiana Fructans on Mucus Production and Morphology Changes in Colonic Epithelium Cell of Healthy Wistar Rats

The beneficial health of evaluating prebiotic effect by the consumption of Agave salmiana fructans (A. salmiana fructans) was assessed in the epithelium of the cecum and proximal colon of Wistar rats fed at different doses for 35 days with regards to mucus production, morphological cell changes, and the serum concentration of tumor necrosis factor-α (TNF-α). Results showed a significant increase in mucus-secreting cells (P < 0.05) and a normal structure with preserved crypts, without morphological damage to colonic cells for a dose of 12.5% (w/w) with respect to the control and the other doses evaluated. The concentration of pro-inflammatory cytokine TNF-α was decreased significantly (P < 0.05) in the groups with doses of 10 and 12.5% (w/w) at 7 and 35 days, respectively. This effect was positively correlated with the reduction of inflammation in epithelial cells. This study provides direct evidence of the effects of the A. salmiana fructans on the colonic epithelium, demonstrating that a diet supplemented with 12.5% of fructans for 35 days exerts health benefits through the strengthening of the mucosa layer, which favors the adherence of the bacterial population and suppresses inflammation.

Production and Physicochemical Properties of Food-Grade High-Molecular-Weight Lactobacillus Inulin

Inulin has been widely applied in food, pharmaceuticals, and many other fields because of its versatile physicochemical properties and physiological functions. Previous research showed that inulosucrase from microorganisms could produce higher-molecular-weight inulin than vegetal inulin. Herein, a food-grade recombinant Bacillus subtilis expression system was constructed to produce inulosucrase from Lactobacillus gasseri DSM 20604 without antibiotic resistance genes. The produced inulosucrase was used to biosynthesize inulin with an average molecular weight of 5.8 × 10⁶ Da. The physicochemical properties of the produced Lactobacillus inulin were evaluated including microstructure, thermal characteristics, crystallinity, rheological behaviors, and storage stability. By comparing with vegetal inulin and other polymers, the biosynthesized microbial inulin showed some superior properties, such as better gel-forming capability and storage stability in aqueous solution than vegetal inulin. These results opened up possibilities for further investigations aimed at developing microbial inulin in the food industry.

Effect of Durio zibethinus rind polysaccharide on functional constipation and intestinal microbiota in rats

The prevalence of constipation increases rapidly with the increased pressure of some people's life, which seriously affects the quality of life in related patients. In this study, the improvement of functional constipation by Durio zibethinus Murr rind polysaccharide (DZMP) and the effects of DZMP on intestinal microbiota were investigated in a constipation model of Sprague-Dawley (SD) rats established by loperamide hydrochloride. Results showed that DZMP at 200 mg/kg could significantly (P < 0.05) increase the intestinal transit rate, motilin, gastrin, substance P levels and concentration of short-chain fatty acids (SCFAs), reduce the somatostatin levels and improve the gastrointestinal peristalsis of rats. Sequencing showed that the Lachnospiraceae-NK4A136-group in the rats given 200 mg/kg DZMP (16.07%) was significantly higher than that of the model group (10.13%), while the Desulfovibrio was lower (2.99%) than that of the model group (4.19%). Principal co-ordinates analysis (PcoA) revealed a significant difference in intestinal microbiota composition between the model group and the high-dose DZMP group (200 mg/kg). The results demonstrated that DZMP has a regulatory effect of treating functional constipation and regulating intestinal flora in rats.

Fermentable carbohydrate intake and food avoidance behaviour in elderly patients with irritable bowel syndrome: A case report

Background: Fermentable carbohydrates or FODMAPs (Fermentable Oligo-, Di-, Monosaccharides, and Polyols) are short-chained, poorly absorbed carbohydrates which trigger gastrointestinal symptoms causing pain, bloating, distension, diarrhea, and constipation in Irritable Bowel Syndrome (IBS) patients. This debilitating condition has an impact on the quality of life of patients. In addition, due to lack of dietary intervention, it can result in food restriction to alleviate symptoms as patients avoid a wide variety of food and beverages. Objective: To compare FODMAP and nutrient intake, food avoidance behavior and quality of life in 2 long standing patients with IBS. Methods: Patients were selected on the basis of being diagnosed with IBS by a gastroenterologist. A 24-hour dietary recall with multiple pass method was used to assess intake. FODMAP intake was determined using published data. Symptom severity and quality of life was measured using a validated questionnaire. Meanwhile, food avoidance was assessed using a dietary trigger piloted questionnaire. Results: Two female Chinese patients with severe gastrointestinal symptoms were selected for this case series. Patient 1 was a 75-year-old female presenting with constipation-predominant IBS and patient 2 was a 61-year-old presenting with diarrhea-predominant IBS. Patient 1 had a higher energy intake: 2198 kcal, and FODMAP intake 10.6g/d, compared to patient 2 with an energy and FODMAP intake of 1800 kcal and 3.6g/d respectively. Both patients avoided a wide of range of food groups including cereals and grains, animal products, dairy and spicy foods. They also reported reduced scores for quality of life. Conclusion: Both patients had low intake of calcium as a result of food avoidance. This highlights the importance of appropriate and timely dietary intervention to this group of patients, to promote improved symptom management without compromising nutrient intake.

AN INNOVATIVE TECHNOLOGY OF WAFFLES WITH FUNCTIONAL PROPERTIES

The high-priority tasks of today’s confectionery industry include the development and introduction of functional-purpose confections. These products are supposed to be of high technological qualities, be effective in production to the extent possible, and have physiological functional properties due to the physiologically valuable ingredients in their composition. These ingredients include the synbiotic complex composed of probiotics (bifidobacteria, lactobacilli) and prebiotics (inulin and lactulose). This complex has been studied in this research. The paper gives reasons why waffles with fatty fillings are the ones to which the synbiotic complex should be added. It has been established what mass fraction of the ingredients at what stage of fatty filling production should be added. It has been studied how the synbiotic complex affects the structural and mechanical properties of the fatty filling: its effective viscosity, adhesive strength, and critical shear stress. It has been found that the maximum shear rate that still allows obtaining a high-quality filling is 5.4 s-1. The specific pull-off force of the fatty filling with the synbiotic added becomes lower compared to that of the control sample. This helps reduce the energy consumed in the course of moulding waffles. An innovative manufacturing technology for waffles with synbiotic supplements has been developed and proved practical. It includes the stages of preparing microencapsulated microorganisms and adding prebiotics, and provides the technological parameters of fatty filling preparation. It has been established that the synbiotic included into the composition of the new fatty filling decreases the maturation of waffle blocks by 40–45%, and allows reducing the layer of filling to 1–1.5 mm. It has been proven that the synbiotic complex as an ingredient in the fatty filling of waffles will allow developing and manufacturing confections that improve human microflora. These new specialised products will be socially significant, as they will help solve a topical and important task of the confectionery industry: prevent gastrointestinal diseases.

Whole-Transcriptome Analysis Unveils the Synchronized Activities of Genes for Fructans in Developing Tubers of the Jerusalem Artichoke

Helianthus tuberosus L., known as the Jerusalem artichoke, is a hexaploid plant species, adapted to low-nutrient soils, that accumulates high levels of inulin in its tubers. Inulin is a fructose-based polysaccharide used either as dietary fiber or for the production of bioethanol. Key enzymes involved in inulin biosynthesis are well known. However, the gene networks underpinning tuber development and inulin accumulation in H. tuberous remain elusive. To fill this gap, we selected 6,365 expressed sequence tags (ESTs) from an H. tuberosus library to set up a microarray platform and record their expression across three tuber developmental stages, when rhizomes start enlarging (T0), at maximum tuber elongation rate (T3), and at tuber physiological maturity (Tm), in "VR" and "K8-HS142"clones. The former was selected as an early tuberizing and the latter as a late-tuberizing clone. We quantified inulin and starch levels, and qRT-PCR confirmed the expression of critical genes accounting for inulin biosynthesis. The microarray analysis revealed that the differences in morphological and physiological traits between tubers of the two clones are genetically determined since T0 and that is relatively low the number of differentially expressed ESTs across the stages shared between the clones (93). The expression of ESTs for sucrose:sucrose 1-fructosyltransferase (1-SST) and fructan:fructan 1-fructosyltransferase (1-FFT), the two critical genes for fructans polymerization, resulted to be temporarily synchronized and mirror the progress of inulin accumulation and stretching. The expression of ESTs for starch biosynthesis was insignificant throughout the developmental stages of the clones in line with the negligible level of starch into their mature tubers, where inulin was the dominant polysaccharide. Overall, our study disclosed candidate genes underpinning the development and storage of carbohydrates in the tubers of two H. tuberosus clones. A model according to which the steady-state levels of 1-SST and 1-FFT transcripts are developmentally controlled and might represent a limiting factor for inulin accumulation has been provided. Our finding may have significant repercussions for breeding clones with improved levels of inulin for food and chemical industry.

Changes in stool frequency following chicory inulin consumption, and effects on stool consistency, quality of life and composition of gut microbiota

Inulin is a soluble dietary fibre, also classified as a prebiotic, extracted from chicory roots. The present study aimed to determine the effect of consumption of native chicory inulin on the stool frequency of middle-aged to older adults (40-75 years old) with uncomfortably but not clinically relevant low stool frequency, specified as two to four days without bowel movements per week. Two randomised, double blind, placebo-controlled crossover trials were conducted using similar protocols in differing populations. Trial A was conducted in Amsterdam, The Netherlands and subsequently Trial B was conducted in Newcastle, United Kingdom. Both trials involved supplementation for 5 weeks with 10 g per day of inulin or placebo, a washout period of 2 weeks, and then crossed over to receive the other treatment. In Trial B, faecal gut microbiota composition was assessed using 16S rRNA gene sequencing. In Trial A, which 10 volunteers completed, the stool frequency was significantly increased to an average 4.9 ± 0.23 (SEM) times per week during inulin periods versus 3.6 ± 0.25 in the periods with placebo (p = 0.01). In contrast, in Trial B which 20 volunteers completed, there was no significant effect of the inulin on stool frequency (7.5 ± 2.1 times per week with inulin, 8.1 ± 3.0 with placebo, p = 0.35). However, many subjects in Trial B had a stool frequency >5 per week also for the placebo period, in breach of the inclusion criteria. Combining the data of 16 low stool frequency subjects from Trials A and B showed a significant effect of inulin to increase stool frequency from 4.1 to 5.0 per week (p = 0.032). Regarding secondary outcomes, stool consistency was significantly softer with inulin treatment compared to placebo periods, it increased 0.29 on the Bristol stool scale (p = 0.008) when data from all subjects of Trials A and B were combined. No other differences in bowel habit parameters due to inulin consumption were significant. None of the differences in specific bacterial abundance, alpha or beta diversity were significant, however the trends were in directions consistent with published studies on other types of inulin. We conclude that 10 g per day of native chicory inulin can increase stool frequency in subjects with low stool frequency.

Impact of Milk Fortification on the Microbiological and Physicochemical Properties of Set-Type Skimmed Yoghurt Using Three Commercial Soluble Prebiotics

The impact of milk fortification on the microbiological and physicochemical properties of a set-type skimmed yoghurt using three commercial soluble prebiotics (inulin, iso-malto-oligosaccharides, and xylo-oligosaccharides) at either 3 or 5 g/kg was assessed. The three prebiotics had an insignificant impact on yoghurt fermentation because all yoghurt samples had similar titratable acidity and similar pH values after their lactic acid fermentation. Regarding the control yoghurt samples without prebiotics usage, the prebiotics-fortified yoghurt samples showed no difference in their main chemical compositions, hardness, syneresis extent, and apparent viscosity (p > 0.05), but had a slightly higher lactic acid content and a viable quantity of starter strains. All yoghurt samples had the same acetic acid content, while propionic and butyric acids were not produced. Yoghurt storage at 4 C for 21 d gave these yoghurt samples decreased pH values and a viable quantity of starter strains (especially Lactobacillus delbrueckii subsp. bulgaricus) and unchanged acetic acid; however, it increased lactic acid contents. Overall, prebiotics fortification up to 5 g/kg had a completely insignificant impact on the fermentation and quality attributes of yoghurt samples but could possibly improve the health of consumers due to higher dietary fibers and starter strain populations.