Non-digestible Carbohydrates Research Articles

From Structure to Function: How Prebiotic Diversity Shapes Gut Integrity and Immune Balance

The microbiota stability, diversity, and composition are pillars for an efficient and beneficial symbiotic relationship between its host and itself. Microbial dysbiosis, a condition where a homeostatic bacterial community is disturbed by acute or chronic events, is a predisposition for many diseases, including local and systemic inflammation that leads to metabolic syndrome, diabetes, and some types of cancers. Classical dysbiosis occurs in the large intestine. During this period, pathogenic strains can multiply, taking advantage of the compromised environment. This overgrowth triggers an exaggerated inflammatory response from the human immune system due to the weakened integrity of the intestinal barrier. Such inflammation can also directly influence higher polyp formation and/or tumorigenesis. Prebiotics can be instrumental in preventing or correcting dysbiosis. Prebiotics are molecules capable of serving as substrates for fermentation processes by gut microorganisms. This can promote returning the intestinal environment to homeostasis. Effective prebiotics are generally specific oligo- and polysaccharides, such as FOS or inulin. However, the direct effects of prebiotics on intestinal epithelial and immune cells must also be taken into consideration. This interaction happens with diverse prebiotic nondigestible carbohydrates, and they can inhibit or decrease the inflammatory response. The present work aims to elucidate and describe the different types of prebiotics, their influence, and their functionalities for health, primarily focusing on their ability to reduce and control inflammation in the intestinal epithelial barrier, gut, and systemic environments.

Health Benefits of Prebiotics, Probiotics, Synbiotics, and Postbiotics.

The trillions of microbes that constitute the human gut microbiome play a crucial role in digestive health, immune response regulation, and psychological wellness. Maintaining gut microbiota is essential as metabolic diseases are associated with it. Functional food ingredients potentially improving gut health include prebiotics, probiotics, synbiotics, and postbiotics (PPSPs). While probiotics are living bacteria that provide health advantages when ingested sufficiently, prebiotics are non-digestible carbohydrates that support good gut bacteria. Synbiotics work together to improve immunity and intestinal health by combining probiotics and prebiotics. Postbiotics have also demonstrated numerous health advantages, such as bioactive molecules created during probiotic fermentation. According to a recent study, PPSPs can regulate the synthesis of metabolites, improve the integrity of the intestinal barrier, and change the gut microbiota composition to control metabolic illnesses. Additionally, the use of fecal microbiota transplantation (FMT) highlights the potential for restoring gut health through microbiota modulation, reinforcing the benefits of PPSPs in enhancing overall well-being. Research has shown that PPSPs provide several health benefits, such as improved immunological function, alleviation of symptoms associated with irritable bowel disease (IBD), decreased severity of allergies, and antibacterial and anti-inflammatory effects. Despite encouraging results, many unanswered questions remain about the scope of PPSPs' health advantages. Extensive research is required to fully realize the potential of these functional food components in enhancing human health and well-being. Effective therapeutic and prophylactic measures require further investigation into the roles of PPSPs, specifically their immune-system-modulating, cholesterol-lowering, antioxidant, and anti-inflammatory characteristics.

Effect of Comparable Carbon Chain Length Short- and Branched-Chain Fatty Acids on Adipokine Secretion from Normoxic and Hypoxic Lipopolysaccharide-Stimulated 3T3-L1 Adipocytes.

Background: Microbial fermentation of non-digestible carbohydrates and/or protein produces short-chain fatty acids (SCFA), whereas branched-chain fatty acids (BCFA) are produced from protein fermentation. The effects of individual SCFA and BCFA of comparable carbon chain length on adipocyte inflammation have not been investigated. Objective: To compare the effects of SCFA and BCFA on inflammatory mediator secretion in an adipocyte cell culture model designed to recapitulate obesity-associated adipocyte inflammation under normoxic and hypoxic conditions. Methods: The 3T3-L1 adipocytes were cultured (24 h) without (Control, Con) and with 1 mmol/L of SCFA (butyric acid (But) or valeric acid (Val)) or 1 mmol/L of BCFA (isobutyric acid (IsoBut) or isovaleric acid (IsoVal)) and were unstimulated (cells alone, n = 6/treatment), or stimulated with 10 ng/mL lipopolysaccharide (LPS, inflammatory stimulus, n = 8/treatment) or 10 ng/mL LPS + 100 µmol/L of the hypoxia memetic cobalt chloride (LPS/CC, inflammatory/hypoxic stimulus, n = 8/treatment). Results: Compared to Con + LPS, But + LPS reduced secreted protein levels of interleukin (IL)-1β, IL-6, macrophage chemoattractant protein (MCP)-1/chemokine ligand (CCL)2, MCP3/CCL7, macrophage inflammatory protein (MIP)-1α/CCL3 and regulated upon activation, normal T cell expressed, and secreted (RANTES)/CCL5 and decreased intracellular protein expression of the ratio of phosphorylated to total signal transducer and activator of transcription 3 (STAT3) and nuclear factor kappa B (NFκB) p65 (p < 0.05). Val + LPS reduced IL-6 secretion and increased MCP-1/CCL2 secretion compared to Con + LPS and exhibited a different inflammatory mediator secretory profile from But + LPS (p < 0.05), indicating that individual SCFA exert individual effects. There were no differences in the secretory profile of the BCFA IsoBut + LPS and IsoVal + LPS (p > 0.05). Alternatively, under inflammatory hypoxic conditions (LPS/CC) Val, IsoVal, and IsoBut all increased secretion of IL-6, MCP-1/CCL2 and MIP-1α/CCL3 compared to Con (p < 0.05), whereas mediator secretion did not differ between But and Con (p > 0.05), indicating that the proinflammatory effects of SCFA and BCFA was attenuated by But. Interestingly, But + LPS/CC decreased STAT3 activation versus Con + LPS/CC (p < 0.05). Conclusions: The decreased secretion of inflammatory mediators that is attributable to But highlights the fact that individual SCFA and BCFA exert differential effects on adipocyte inflammation under normoxic and hypoxic conditions.

Phytochemicals and Functional Properties of Pitaya Juice Powders.

Crassulacean acid metabolism plants, such as Stenocereus spp., are climate warming-resilient crops used as food and for by-products elaboration in arid and semi-arid agroecosystems. A few studies on secondary metabolites have been conducted in pitayo fruit (PF), but there are no reports of these compounds in juice powders (JP) with (JPS) or without seeds (JPWS). This study was devoted to characterizing the juice powders (JPS and JPWS) of five pitayas with different flesh colors with regard to some phytochemical and functional attributes. The study was conducted with a completely random design with factorial arrangement in treatments (PF × JP). Differences among pitayas were related to peel and flesh color attributes. Except for soluble dietary fiber, the remainder of the non-digestible carbohydrates were greater in JPS than in JPWS of all pitayas. Phenols and flavonoids were found to be the highest in the JPWS of all pitayas, whereas total saponins were the highest in JPS of the 'Pink' pitaya. The JPWS of the 'Yellow' and 'Reddish-Purple' pitayas had the highest content of betaxanthins and indicaxanthins, respectively. Antioxidant capacity was the highest in JPS of 'Reddish-Purple' and 'Pink' pitayas. Except for some phenolic compounds, the study suggests that pitayas' JPS would benefit human health when freshly consumed or as elaborated by-products.

Rethinking the classification of non-digestible carbohydrates: Perspectives from the gut microbiome.

Clarification is required when the term "carbohydrate" is used interchangeably with "saccharide" and "glycan." Carbohydrate classification based on human digestive enzyme activities brings clarity to the energy supply function of digestible sugars and starch. However, categorizing structurally diverse non-digestible carbohydrates (NDCs) to make dietary intake recommendations for health promotion remains elusive. In this review, we present a summary of the strengths and weaknesses of the traditional dichotomic classifications of carbohydrates, which were introduced by food chemists, nutritionists, and microbiologists. In parallel, we discuss the current consensus on commonly used terms for NDCs such as "dietary fiber," "prebiotics," and "fermentable glycans" and highlight their inherent differences from the perspectives of gut microbiome. Moreover, we provide a historical perspective on the development of novel concepts such as microbiota-accessible carbohydrates, microbiota-directed fiber, targeted prebiotics, and glycobiome. Crucially, these novel concepts proposed by multidisciplinary scholars help to distinguish the interactions between diverse NDCs and the gut microbiome. In summary, the term NDCs created based on the inability of human digestive enzymes fails to denote their interactions with gut microbiome. Considering that the gut microbiome possesses sophisticated enzyme systems to harvest diverse NDCs, the subclassification of NDCs should be realigned to their metabolism by various gut microbes, particularly health-promoting microbes. Such rigorous categorizations facilitate the development of microbiome-targeted therapeutic strategies by incorporating specific types of NDCs.

A review of current analytical methods for the determination of dietary fiber in food

Fiber benefits health and is an essential requirement in the body's daily diet. The definition of fiber has been evolving over the past 70 years. Initially, the definition of fiber focused only on plant cell walls (cellulose, hemicellulose, pectin, cutin, glycoprotein) and intracellular storage and secretion substances (gum, mucilage). More recently, the world has focused on resistant starch and oligosaccharides. The CODEX definition of dietary fiber includes all non-digestible carbohydrate polymers with a degree of polymerization of 3 or higher, provided that they benefit health. Fiber has many components, requiring the development of different methods to analyze components such as fructo-oligosaccharide, galacto-oligosaccharide, polydextrose, resistant maltodextrin, resistant starch, etc. A series of AOAC methods have been developed to explore different types of fiber, and these methods are still valid and widely used. For the analysis of total fiber content, the enzymemass method according to Prosky (AOAC 985.29) was considered the gold standard when it was first published. However, this method only determines a part of the fiber. When adding up the specific fiber components calculated from different methods, some types of fiber are double counting. Therefore, the method for determining total fiber is constantly updated and revised. The Enzymatic-Gravimetric-Liquid Chromatography method has been developed and can fully determine the components of dietary fiber; the newly published updated version is AOAC 2022.01.

46 Feeding the weaned pig gut and beyond with non-nutritional additives

Abstract Weaning imposes simultaneous stress, resulting in reduced growth performance, increased susceptibility to diseases, and increased morbidity and mortality in weaned pigs. Weaning stress can induce negative changes in the intestine, including damaged intestinal integrity, disturbed digestive and absorptive capacity, increased intestinal oxidative stress, and microbial dysbiosis. Improving intestinal development and health is critically important for enhancing disease resistance and overall health of weaned pigs. This, in turn, can increase their survival rate during this vulnerable stage and improve their productive performance in later stages. A healthy gut may include, but is not limited to, several important features: a healthy proliferation of intestinal epithelial cells, an integrated gut barrier function, a preferable or balanced gut microbiota, and well-developed intestinal mucosa immunity. Burgeoning evidence suggests that many non-nutritional additives can enhance overall intestinal health and beyond by targeting one or several functions of the gut. However, the exact protective mechanisms may vary and are still not completely understood. For example, direct-fed microbials may confer health benefits on the host by producing antimicrobial products, regulating gut microbial profile or immunity, and/or enhancing gut barrier function. Non-digestible carbohydrates and prebiotics exhibit striking impacts on reshaping the composition of gut microbiota in the host by boosting the production of health-promoting bacteria. Phytochemicals, a large variety of secondary plant metabolites, have been known for their broad and promising biological properties, including anti-microbial, antioxidant, and immune-modulating activities. Several short chain fatty acids derivatives aim to target the upper gastrointestinal tract, where the major nutrients are digested and absorbed, to promote intestinal health of pigs. Moreover, butyrate and valerate glycerides exhibit strong in vitro antimicrobial effects against enterotoxigenic Escherichia coli F18, one of the dominant pathogens causing post-weaning diarrhea globally. There are more candidates in the list that have been used in weaned pigs and shown promising results on growth and health promotion. Therefore, increasing our current understanding of non-nutritional additives and their influences on intestinal function during weaning will facilitate the development of more dietary strategies that increase stress resilience of weaned pigs.

Impact of GOS and 2’-FL on the production and structural composition of membrane-associated exopolysaccharides by B. adolescentis and B. infantis

Bifidobacteria, which are increasingly linked to health benefits to the host, produce structurally complex exopolysaccharides which are considered to be effector molecules responsible for health effects. It is currently not clear how the bacterial growth conditions, and especially the carbon source, affect the structural composition of the EPS. Here we present our investigations into the impact of the addition of 2′-fucosyllactose (2’-FL) and galactooligosaccharides (GOS), which are non-digestible carbohydrates added to infant formula, as the sole carbon source during the growth of B. adolescentis and B. infantis. Intriguingly, B. adolescentis produced EPS with larger molecular weights in the presence of GOS or a mixture of GOS/2’-FL. B. infantis showed increased growth levels in the presence of 2’-FL, and also produced an α-1,4-glucan polymer, whose amount was increased when grown on GOS. These findings highlight the species-specific effects of growth conditions on EPS structures.

Dietary therapy of murine primary biliary cholangitis induces hepatocellular steatosis: A cautionary tale.

There is increased interest in utilizing dietary interventions to alter the progression of autoimmune diseases. These efforts are driven by associations of gut microbiota/metabolites with levels of short-chain fatty acids (SCFAs). Propionate is a key SCFA that is commonly used as a food preservative and is endogenously generated by bacterial fermentation of non-digestible carbohydrates in the gut. A thesis has suggested that a diet rich in propionate and other SCFAs can successfully modulate autoimmunity. Herein, we investigated the effect of long-term administration of propionylated high-amylose resistant starches (HAMSP) on the course of murine primary biliary cholangitis. Groups of female ARE-Del mice were fed an HAMSP diet either before or after disease onset. A detailed immunobiological analysis was performed involving autoantibodies and rigorous T-cell phenotyping, including enumeration of T-cell subsets in the spleen, liver, intestinal intraepithelial lymphocytes and lamina propria by flow cytometry. Histopathological scores were used to assess the frequency and severity of liver inflammation and damage to hepatocytes and bile ducts. Our results demonstrate that a long-term propionate-yielding diet re-populated the T-cell pool with decreased naïve and central memory T-cell subsets and an increase in the effector memory T cells in mice. Similarly, long-term HAMSP intake reduced CD4+CD8+ double-positive T cells in intraepithelial lymphocytes and the intestinal lamina propria. Critically, HAMSP consumption led to moderate-to-severe hepatocellular steatosis in ARE-Del mice, independent of the stage of autoimmune cholangitis. Our data suggest that administration of HAMSP induces both regulatory and effector T cells. Furthermore, HAMSP administration resulted in hepatocellular steatosis. Given the interest in dietary modulation of autoimmunity and because propionate is widely used as a food preservative, these data have significant implications. This study also provides new insights into the immunological and pathological effects of chronic propionate exposure.

Prebiotics for Induction and Maintenance of Remission in Inflammatory Bowel Disease: Systematic Review and Meta-Analysis.

Prebiotics are nondigestible carbohydrates fermented by gut bacteria into metabolites that confer health benefits. However, evidence on their role for inflammatory bowel disease (IBD) is unclear. This study systematically evaluated the research on prebiotics for treatment of IBD. A search was performed in PubMed, Embase, Cochrane, and Web of Science. Eligible articles included randomized controlled trials or prospective observational studies that compared a prebiotic with a placebo or lower-dose control in patients with IBD. Meta-analyses were performed using random-effects models for the outcomes of clinical remission, clinical relapse, and adverse events. Seventeen studies were included. For induction of clinical remission in ulcerative colitis (UC), the fructooligosaccharide (FOS) kestose was effective (relative risk, 2.75, 95% confidence interval, 1.05-7.20; n = 40), but oligofructose-enriched inulin (OF-IN) and lactulose were not. For maintenance of remission in UC, germinated barley foodstuff trended toward preventing clinical relapse (relative risk, 0.40; 95% confidence interval, 0.15-1.03; n = 59), but OF-IN, oat bran, and Plantago ovata did not. For Crohn's disease, OF-IN and lactulose were no different than controls for induction of remission, and FOS was no different than controls for maintenance of remission. Flatulence and bloating were more common with OF-IN; reported adverse events were otherwise similar to controls for other prebiotics. Prebiotics, particularly FOS and germinated barley foodstuff, show potential as effective and safe dietary supplements for induction and maintenance of remission in UC, respectively. The overall certainty of evidence was very low. There would be benefit in further investigation on the role of prebiotics as treatment adjuncts for IBD.

Gut microbiota signatures of vulnerability to food addiction in mice and humans

ObjectiveFood addiction is a multifactorial disorder characterised by a loss of control over food intake that may promote obesity and alter gut microbiota composition. We have investigated the potential involvement...

Probing into the impacts of endogenous and exogenous short chain fatty acids (SCFAs) in fish health and growth

Abstract Short-chain fatty acids (SCFAs) are small organic acids exist in the fish gastrointestinal tract, mainly acetate, propionate, and butyrate. These SCFAs are produced through anaerobic fermentation of dietary non-digestible carbohydrates by gut microbes. Though enough studies have been devoted to showcasing the potential of SCFAs in human nutrition, the research on their production, potential, and existence in fish has been comparatively limited until recently. This review aims to provide a comprehensive overview of the current knowledge regarding SCFAs in aquaculture. It starts with commenting on the different sources, such as substrate and microbial species that are responsible for the production of SCFAs and their transportation and ends up depicting the relationship between biofloc technology and SCFAs production. This review also discusses the factors influencing SCFA production, such as environment, diet, and feeding habits of fish. Furthermore, the biological functions of SCFAs have been highlighted, and critical findings were compiled, including immunomodulatory effects, physiological response, gut health, and immunity.

85 The influence of supplementing isolated or intact structural fiber on the physicochemical properties of digesta and fecal consistency of nursery pigs

Abstract In human nutrition, functional fiber refers to isolated non-digestible carbohydrates with physiological roles, while structural fiber pertains to those that are intrinsic and intact in plants. Increasing dietary fiber in post-weaning pig diets has been shown to improve gastrointestinal health and alter fecal consistency. However, minimal research has been conducted on the role of supplementing isolated functional or structural fiber that are chemically insoluble in nursery diets. The experimental objective was to evaluate the effect of functional or structural insoluble fiber supplementation on the physicochemical properties of digesta and feces during the nursery period. A total of 256 newly weaned pigs were randomly assigned to one of four treatments across two replications with 4 pigs per pen and 16 pens per treatment for a 35-d study. The average initial pig body weight (BW) was 5.13 ± 0.65 kg and same sex pens were used and balanced across treatments. Dietary treatments consisted of a control nursery diet (PC), PC with 3% soy hulls (NC), PC with 2% isolated lignocellulose (ISO), and PC with 2% structural lignocellulose (STR). Treatments were fed across phase 1 (d 0-7) and phase 2 (d 7-21) diets, and a common diet was fed in phase 3 (d 21-35). On d 7, 14, 21, 28, and 35, fresh fecal samples were collected to determine water binding capacity (WBC), water swelling capacity (WSC), and fecal dry matter (DM). Fecal scores were also evaluated using a predefined scale (1 = solid; 4 = liquid). On d 21, one pig per pen closest to the mean BW was necropsied, and ileal, cecal, and colonic digesta were collected. Continuous data were analyzed as a linear mixed model (PROC MIXED) with treatment, sex, and period as fixed effects, replicate as a random effect, and initial BW as a covariate where appropriate. Fecal scores were analyzed using a multinomial model in PROC GENMOD and FREQ. Pigs fed ISO and STR tended to have greater fecal DM (24.1%, 24.6%, 25.4%, and 26.29% for PC, NC, ISO, and STR, respectively; P = 0.071). There was a greater proportion of solid and semi-solid feces in pigs fed ISO (P = 0.039). Fecal WBC was greatest in pigs fed PC, with NC and ISO performing intermediately, and STR having the least (2.66, 2.55, 2.50, and 2.39 mL/g of DM for PC, NC, ISO, and STR, respectively; P = 0.071). Fecal WSC increased with time (P &amp;lt; 0.001), but there was no impact of treatment (P = 0.983). Ileal digesta pH was decreased in NC and STR, relative to PC and ISO, (P = 0.007). There tended to be a similar response for cecal pH (P = 0.092). Pigs fed PC tended to have the greatest colonic WBC (P = 0.058). Collectively, supplementing isolated or structural lignocellulose can alter the physicochemical properties of nursery pig feces.

Development of the CE-C4D method for determination of organic acids in infants faeces using an in-house built instrument

Short-chain fatty acids (SCFAs) are a major group of products produced during colonic bacterial fermentation of nondigestible carbohydrates demonstrating several important functions, e.g. regulating the immune system activity or the lipid metabolism. A detailed profile and concentration characterization of SCFAs in infant faeces is essential for expanding knowledge regarding the role of SCFAs in infant physiology and pathophysiology. This research presents the development and validation of a capillary electrophoresis method with a contactless capacitively coupled conductivity detector (CE-C4D) for the analysis of SCFAs and succinic and lactic acids in infant faeces. The study focused on optimizing the background electrolyte, mainly dynamic capillary coating with polybrene, and utilizing cyclodextrins to achieve efficient separation. Validation parameters, such as linearity (0.993 – 0.998), limits of detection and quantification (LOD: 0.10 – 0.89 μg/mL; LOQ: 0.35 – 2.97 μg/mL), intra- and inter-day precision (1.71 – 5.69 % and 1.11 – 12.5 %, respectively), injection repeatability (0.91 – 5.70 %), trueness (-12.8 – 3.80 %), and matrix effect (78.8 – 108.6 %), were assessed and the method was found suitable for the purpose. The demonstrated method was successfully applied to determine nine organic acids in faecal samples.

Effect of Short-Chain Fatty Acids on Inflammatory and Metabolic Function in an Obese Skeletal Muscle Cell Culture Model.

The fermentation of non-digestible carbohydrates produces short-chain fatty acids (SCFAs), which have been shown to impact both skeletal muscle metabolic and inflammatory function; however, their effects within the obese skeletal muscle microenvironment are unknown. In this study, we developed a skeletal muscle in vitro model to mimic the critical features of the obese skeletal muscle microenvironment using L6 myotubes co-treated with 10 ng/mL lipopolysaccharide (LPS) and 500 µM palmitic acid (PA) for 24 h ± individual SCFAs, namely acetate, propionate and butyrate at 0.5 mM and 2.5 mM. At the lower SCFA concentration (0.5 mM), all three SCFA reduced the secreted protein level of RANTES, and only butyrate reduced IL-6 protein secretion and the intracellular protein levels of activated (i.e., ratio of phosphorylated-total) NFκB p65 and STAT3 (p < 0.05). Conversely, at the higher SCFA concentration (2.5 mM), individual SCFAs exerted different effects on inflammatory mediator secretion. Specifically, butyrate reduced IL-6, MCP-1 and RANTES secretion, propionate reduced IL-6 and RANTES, and acetate only reduced RANTES secretion (p < 0.05). All three SCFAs reduced intracellular protein levels of activated NFκB p65 and STAT3 (p < 0.05). Importantly, only the 2.5 mM SCFA concentration resulted in all three SCFAs increasing insulin-stimulated glucose uptake compared to control L6 myotube cultures (p < 0.05). Therefore, SCFAs exert differential effects on inflammatory mediator secretion in a cell culture model, recapitulating the obese skeletal muscle microenvironment; however, all three SCFAs exerted a beneficial metabolic effect only at a higher concentration via increasing insulin-stimulated glucose uptake, collectively exerting differing degrees of a beneficial effect on obesity-associated skeletal muscle dysfunction.

Clinical Uses of Fructooligosaccharides for Gastrointestinal health in the Pediatric Population

Fructooligosaccharides (FOS) are non-digestible carbohydrates that are one of the major classes of bifidogenic oligosaccharides. Studies find that prebiotics such as FOS display health benefits pertaining to but not restricted to the gastrointestinal tract of an infant. This review article aims to discuss the therapeutic potential of FOS for different pediatric gut conditions. FOS in varying concentration has been found to prevent constipation and soften stools; reduce the incidence and severity of diarrhoea; alleviate GI discomfort symptoms such as vomiting and regurgitation. Infants and children seem to tolerate both short and long chain FOS molecules well. Although FOS is beneficial for infant and child health, there is still a need for rigorous clinical trials and long term follow up studies to understand if FOS supplemented in infancy can confer long term effects in adulthood.

Alkali treatment of maize bran affects utilization of arabinoxylan and other non-digestible carbohydrates by the human gut microbiota in vitro in a dose-dependent manner

Alkali treatment of maize bran can break ferulate cross-linking and increase utilization of alkali-solubilized arabinoxylan (AX) by the human gut microbiome. However, it is not known how alkali treatment affects the utilization of AX and other non-digestible carbohydrates (NDC) that remain insoluble after alkali treatment, or how varying degrees of alkali treatment affect NDC fermentation. Therefore, maize bran was treated with alkali ranging from 0 to 1.25 M NaOH, neutralized, and then subjected to in vitro digestion and fermentation using human fecal microbiomes. Increasing alkali concentration progressively increased water solubility of NDC, especially AX, and increased microbial fermentation of water-soluble AX (p < 0.001) during fermentation; however, there was a decrease in fermentation of insoluble AX and NDC (p < 0.001). Across microbiomes, more acetate (p = 0.004) and propionate (p = 0.018), but less butyrate (p < 0.001), were produced as alkali treatment of maize bran increased. Higher alkali treatments increased the abundances of Bifidobacterium (q < 0.001), Bacteroides (q = 0.0015), Faecalibacterium (q < 0.001), and several genera in the Bacilli class (q < 0.001), while decreasing Bilophila (q < 0.001), Butyricicoccus (q < 0.001), and several Lachnospiraceae (q < 0.001). Soluble but not insoluble NDC utilization was improved by extracting residual free phenolic compounds from alkali-treated maize bran (p = 0.005 and p = 0.39, respectively). In conclusion, alkali makes maize bran AX more water soluble and fermentable, but it has a negative impact on insoluble AX and NDC utilization, which reduces butyrate production by the microbiome due to decreases in Butyricicoccus and some Lachnospiraceae.

Effect of prebiotics, probiotics, and synbiotics on gut microbiome in diabetes among coastal communities

Cutting-edge research on oceans and human health is enhancing our comprehension of disease-causing organisms in coastal ecosystems. Coastal areas are affected by pollution resulting from the changes in hydrology and land utilization. In the coastal population, an elevated incidence of diabetes was observed. Diabetes mellitus is a prominent metabolic disease that is causing major burdens for patients as well as physicians. Diabetes is an intricate condition that encompasses several molecular pathways associated with the gut microbiome. The gut microbiome significantly influences the permeability of the gastrointestinal mucosa. Alterations in the wide range of gut microbiomes have been associated with various health issues including diabetes. The two major contributors to type 2 diabetes are insulin resistance and inflammation which may result in metabolic dysregulation due to dysbiosis. Due to gut dysbiosis, diabetes may show high prevalence in individuals living in coastal areas. The correlation between dysbiosis and diabetes can be made, especially considering probiotics have been demonstrated to have some impact in helping diabetic patients with their interrupted metabolism revert to normal. Probiotic intake has reportedly resulted in improved metabolic control among patients with type 2 diabetes. Prebiotics can be non-digestible carbohydrates that are naturally extracted or synthetically produced. Uses of synbiotics show a synergistic impact on type 2 diabetes by altering the gut environment. In coastal communities, the potential effects of probiotic, prebiotic, and synbiotic therapy on the gut microbiome of diabetic patients have been investigated. Although these therapies have demonstrated encouraging results in coastal areas, more research is needed to fully understand their implications for controlling diabetes in this setting. In this review, we describe the role of the gut microbiome in diabetes patients residing in coastal regions and the underlying mechanisms that existed for analysing and predicting the function of the microbiome in diabetic people. The role of pre, pro, and synbiotics in type 1 and type 2 diabetes are precisely summarized. Keywords: Type 1 diabetes, gut microbiome, type 2 diabetes, coastal region, dysbiosis, prebiotics, synbiotics, probiotics.

Physiologic Effects of Isolated or Synthetic Dietary Fiber in Children: A Scoping Review

BackgroundFiber is an integral part of a healthy diet. Studies have shown that the fiber intake in children is below adequate amounts, leading to adverse health outcomes. ObjectivesThis study aimed to perform a scoping review to assess the available evidence for the impact of isolated and synthetic dietary fiber on children’s health outcomes. MethodsA systematic literature search was conducted in Ovid Medline, Ovid Global Health, Embase, and Cochrane Library via Wiley to identify randomized controlled trials (RCTs) in healthy children aged 1–18 y at baseline who consumed added, isolated, or synthetic dietary fiber. The outcomes of interest were categorized based on the Food and Drug Administration’s guidance for industry on nondigestible carbohydrates and the Vahouny Fiber Symposium criteria, which included reduced fasting blood, glucose, total and/or LDL cholesterol concentrations, attenuation of postprandial glycemia/insulinemia, increased fecal bulk/laxation, reduced transit time, weight loss/reduction in adiposity, reduced energy intake from food consumption, increased satiety, bone health/enhanced mineral absorption, and blood pressure. We also cataloged additional reported outcomes. ResultsOf 3837 randomized controlled parallel or crossover trials screened at the abstract level, 160 were eligible for full-text review, and 32 included for data extraction. This scoping review presents analysis of data from 32 RCTs in children who were healthy, overweight/obese or had mild hypercholesterolemia. Inulin-type fructans (41%) and psyllium (22%) were the most frequently administered fiber types, with weight/adiposity, markers of lipid metabolism (41%), and bone-related markers (38%) being the most frequently reported health outcomes. Only a few RCTs have investigated the effects of laxation (9%), and none specifically studied the impact of fiber on reducing postprandial glycemia/insulinemia. ConclusionsThis scoping review demonstrates sufficient evidence for conducting systematic reviews and meta-analyses for several outcomes. Evidence gaps remain on the impact of isolated fibers on outcomes such as laxation, colonic transit time, and postprandial glycemia/insulinemia in children.

A novel “microbiota-host interaction model” to study the real-time effects of fermentation of non-digestible carbohydrate (NDCs) on gut barrier function

In this study, an in vitro co-culture model using an electric cell-substrate impedance sensing system (ECIS) for testing the impact of real-time fermentation of non-digestible carbohydrates (NDCs) by the intestinal microbiota on gut barrier function was established. We applied Lactobacillus plantarum WCFS1 as a model intestinal bacterium and alginate-pectin as immobilization polymers as well as a source of NDCs to determine the impact of pectin fermentation on the barrier function of T84 gut epithelial cells. In the first design, L. plantarum WCFS1 was encapsulated in an alginate capsule followed by embedding in an agar layer to mimic a firm mucus layer that might be present in the colon. In this experimental design, the presence of the agar layer interfered with the transepithelial electrical resistance (TEER) measurement of T84 cells. Subsequently, we removed the agar layer and used encapsulated bacteria in an alginate gel and found that the TEER measurement was adequate. The encapsulation of the L. plantarum WCFS1 does avoid direct contact with cells. Also, the encapsulation system allows higher amounts of packing densities of L. plantarum WCFS1 in a limited space which can limit the oxygen concentration within the capsule and therefore create anaerobic conditions. To test this design, T84 cells were co-incubated with L. plantarum alginate-capsules supplemented with graded loads of fermentable pectin (0, 4, and 8 mg/ml per capsule) to investigate the effect of pectin fermentation on gut barrier function. We observed that as the pectin content in the L. plantarum capsules increased, pectin showed a gradually stronger protective effect on the TEER of the gut epithelium. This could partly be explained by enhanced SCFA production as both lactate and acetate were enhanced in L. plantarum containing alginate capsules with 8 mg/ml pectin. Overall, this newly designed in vitro co-culture model allows for studying the impact of bacteria-derived fermentation products but also for studying the direct effects of NDCs on gut barrier function in a relatively high-throughput way.