Mechanisms of Degradation of Insoluble Dietary Fiber from Coconut Chips by Ultra-High Pressure.

Coconut chips are a popular leisure food, but the residual crumbly feeling after chewing affects the eating experience. To address this problem, we investigated the mechanism of degradation of insoluble dietary fiber (IDF) from coconut chips by ultra-high pressure (UHP). The optimal conditions for UHP treatment were 100 MPa and 40 min. After UHP treatment, the hardness decreased by 60%, and the content of soluble dietary fiber (SDF) increased by 55%. So far, the meaning of SDF has not been defined. The microstructure of IDF was damaged and the surface was rough. There was no obvious change in the chemical structure. The position of the characteristic diffraction peaks was basically unchanged, but the crystallinity dropped by almost three times. The thermal stability decreased, and the composition of the monosaccharides changed. Together, UHP treatment can improve the problem of the residual crumbly feeling after chewing coconut chips and improve the quality of the product.

Effects of Prebiotic Dietary Fibers on the Stimulation of the Mucin Secretion in Host Cells by In Vitro Gut Microbiome Consortia.

The gastrointestinal microbiota are important for human health. Dietary intake may modulate the composition and metabolic function of the gut microbiome. We examined how the breakdown of prebiotic dietary fibers by the gut microbiome affects mucin secretion by intestinal epithelial cells. Metagenomic analyses of in vitro gut microbiome consortia revealed taxonomic profiles and genetic diversity of carbohydrate-active enzymes that digest polysaccharides. Two independent consortia exhibited different abilities to produce acetic acid, propionic acid, and butyric acid via the fermentation of polysaccharides derived from dietary fibers of grains and mushrooms. Although acetic acid generally had the highest concentration, the ratios of butyric acid and propionic acid to acetic acid varied depending on the polysaccharide source. These short-chain fatty acids affected morphological differentiation and mucin secretion in HT-29 human intestinal epithelial cells. These results suggest that prebiotic dietary fibers can be digested and metabolized by the gut microbiome to short-chain fatty acids, which can affect gut epithelial cells both directly and indirectly via the modulation of the gut microbiota and their enzymes.

The pectin metabolizing capacity of the human gut microbiota.

The human gastrointestinal microbiota, densely populated with a diverse array of microorganisms primarily from the bacterial phyla Bacteroidota, Bacillota, and Actinomycetota, is crucial for maintaining health and physiological functions. Dietary fibers, particularly pectin, significantly influence the composition and metabolic activity of the gut microbiome. Pectin is fermented by gut bacteria using carbohydrate-active enzymes (CAZymes), resulting in the production of short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate, which provide various health benefits. The gastrointestinal microbiota has evolved to produce CAZymes that target different pectin components, facilitating cross-feeding within the microbial community. This review explores the fermentation of pectin by various gut bacteria, focusing on the involved transport systems, CAZyme families, SCFA synthesis capacity, and effects on microbial ecology in the gut. It addresses the complexities of the gut microbiome's response to pectin and highlights the importance of microbial cross-feeding in maintaining a balanced and diverse gut ecosystem. Through a systematic analysis of pectinolytic CAZyme production, this review provides insights into the enzymatic mechanisms underlying pectin degradation and their broader implications for human health, paving the way for more targeted and personalized dietary strategies.

Effectiveness of High-Fiber, Plant-Based Diets in Reducing Cardiovascular Risk Factors Among Middle-Aged and Older Adults: A Systematic Review.

Cardiovascular disease (CVD) is a prominent contributor to morbidity and mortality, particularly in the middle-aged and elderly population. Plant-based, high-fiber diets high in fruits, vegetables, whole grains, legumes, and nuts can significantly lower CVD risk factors. This systematic review aims to assess how effectively diet improves cardiovascular health in this demographic. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria, we thoroughly searched PubMed, Google Scholar, ScienceDirect, Cochrane Library, and ClinicalTrials.gov, explicitly focusing on papers published in English. The review identified 10 pertinent papers, including three systematic reviews, one randomized-controlled trial (RCT), two observational studies, and four review articles demonstrating significant improvements in blood pressure, cholesterol levels, and glycemic management associated with high-fiber plant-based diets (PBDs). The research specifically emphasized the significance of dietary fiber in decreasing low-density lipoprotein (LDL) cholesterol, enhancing insulin sensitivity, and reducing systemic inflammation. These data support the concept that PBDs high in fiber can effectively lower CVD risk factors. However, limitations such as self-reported dietary intake and variability in adherence were noted. In conclusion, high-fiber PBDs are a viable strategy for managing and preventing CVD in middle-aged and older adults. Future research should focus on long-term adherence, the comparative benefits of different plant-based foods, and developing personalized dietary recommendations to optimize cardiovascular health outcomes in this population.

Study on the prebiotic effects of insoluble crude and fine fibers of wheat bran after simulated digestion in vitro.

This study aims to evaluate the probiotic effects of insoluble crude and fine fibers of wheat bran on the intestine after simulated in vitro digestion. It was found that the particle size distribution of modified fine wheat bran (MWB) was significantly smaller than that of natural crude wheat bran (NWB). MWB had a looser texture and more porous structure. The dry matter digestibility and organic matter digestibility of MWB were 58.60 % and 59.05 %, which were significantly higher than that of NWB (53.64 % and 54.13 %). More SDF and free polyphenol were released from the MWB. At 12 h of fermentation, the SDF content of the MWB was 3.76 g/100 g, significantly higher than NWB (3.40 g/100 g), and the free polyphenol was 9.43 mg/g, significantly higher than NWB (9.01 mg/g). The content of short-chain fatty acids including formic acid, acetic acid, propionic acid, butyrate acid and valerate acid in the samples were significantly higher in MWB than in NWB. Analysis of the microbial flora structure and diversity of the fermentation samples revealed that the relative abundance of Lactobacillus was higher in the MWB group, and was closer to the oligofructose group (FOS) in terms of functional predictions.

Consumption of a Sourdough-Leavened Croissant Enriched with a Blend of Fibers Influences Fasting Blood Glucose in a Randomized Controlled Trial in Healthy Subjects.

BACKGROUND: An incorrect lifestyle, including diet, is responsible for the worldwide dramatic increase in obesity and type 2 diabetes. Increasing dietary fiber consumption may lead to health benefits, and reformulation of bakery products may be a strategy to globally improve the diet. OBJECTIVES: This study aimed to assess the impact of a 2-wk breakfast consumption with a sourdough-leavened croissant containing a blend of dietary fiber from 10 sources (4.8 g/100 g, croissant enriched with dietary fibers [FIBCRO]), compared with a control croissant (dietary fibers 1.3 g/100 g, CONCRO) on daily energy intake, appetite, metabolic variables, and the gut microbiome. METHODS: Thirty-two healthy participants were randomly allocated to 2 groups consuming FIBCRO or CONCRO. Participants self-recorded their diet and appetite through 7-d weighted food diaries and visual analog scales every day over the 2 wk. At baseline and after the intervention, fasting blood and urine samples, and fecal samples were collected beside blood pressure, anthropometry, and body composition. Serum glucose, lipids, C-reactive protein, and insulin according to the official methods and serum dipeptidyl peptidase-4 (DPPIV) activity by photometric method were measured. Polyphenols and urolithins in urines were analyzed by Liquid chromatography-tandem mass spectrometry (LC/MS/MS), whereas gut microbiome in feces by shotgun metagenomics. RESULTS: FIBCRO consumption improved fasting blood glucose compared with CONCRO (mean changes from baseline -2.0 mg/dL in FIBCRO compared with +3.1 mg/dL in CONCRO, P = 0.022), also reducing serum DPPIV activity by 1.7 IU/L (P = 0.01) and increasing urinary excretion of urolithin A-sulfate by 6.9 ng/mg creatinine (P = 0.04) compared with baseline. No further changes in any of the monitored variables or in the gut microbiome were detected. CONCLUSIONS: Results suggested that a 2-wk consumption of a sourdough croissant claimed as "source of dietary fiber" improved fasting glycemia compared with a conventional sourdough croissant in healthy subjects. The reduced serum DPPIV activity and increased bioavailability of urolithin likely contributed to determine that effect independently from gut microbiome changes. This trial was registered at clinicaltrials.gov as NCT04999280.

Gender Difference in the Impact of Total Energy Intake on the Association between Low Fiber Intake and Mental Health in Middle-Aged and Older Adults.

The effect of dietary fiber intake on mental health is controversial. This study aimed to examine the association of fiber intake with mental health in Korean adults. This cross-sectional study included 11,288 participants aged ≥40 years who participated in the Korean Genome and Epidemiology Study (2004-2013). Fiber intake was assessed using a food frequency questionnaire and categorized into sex-specific quintiles. Multiple logistic regression models were used to investigate the association between the lowest quintile of fiber intake and poor mental health. Mental health was assessed using acute stress perception, the Psychosocial Well-Being Index-Short Form, self-rated health, and the Center for Epidemiological Studies-Depression Scale in Korea. Compared to those with higher fiber intake, having the lowest quintile of fiber intake was associated with higher odds of poor mental health risk, a higher risk of high-stress perception, poor psychosocial distress in males, poor psychosocial distress, and depression in females. Low fiber intake had profound negative mental health effects on males with high total energy intake and females with low total energy intake. In conclusion, there is a gender difference in the impact of total energy intake on the deleterious effect of low fiber intake on mental health.

Polysaccharides extracted from tucum-do-cerrado fruits (Bactris setosa Mart) have antineoplastic effects in mice while preserving hepatic gluconeogenesis.

This study investigated the antitumoral, anti-inflammatory and oxidative effects of polysaccharides from tucum (Bactris setosa, TUC) using the Ehrlich carcinoma as a tumor model. Additionally, the glycogen content, cytochrome P levels, and gluconeogenesis from lactate were assessed in the liver of healthy animals. Tumor-bearing female mice were orally treated with 50 and 100 mg.kg-1 of TUC or vehicle, once a day, or with 1.5 mg.kg-1 methotrexate via i.p., every 3 days, along 21 days. Both doses of TUC reduced the tumor weight and volume. In the tumor tissue, it decreased GSH and IL-1ß levels, and increased LPO, NAG, NO and TNF-α levels. The tumor histology showed necrosis and leukocytes infiltration. The metabolic effects of TUC were investigated by measurement of total cytochrome P (CYP) and glycogen in tumor-bearing mice, and by ex vivo liver perfusion on non-bearing tumor male mice, using lactate as gluconeogenic precursor. Metabolically, the hepatic glucose and pyruvate productions, oxygen uptake, and the total CYP concentration were not modified by TUC. Thus, tucum-do-cerrado polysaccharides have antitumor effects through the modulation of oxidative stress and inflammation, without impairing glucose production from lactate in the liver, the main organ responsible for the metabolism of organic and xenobiotic compounds.

Bridging sustainability and industry through resourceful utilization of pea pods- A focus on diverse industrial applications.

The focus on sustainable utilization of agricultural waste is currently a leading area of scientific research, driving significant advancements in technology and circular economy models. The fundamental capacity of bio-based products, bioprocessing techniques, and the crucial involvement of microbial treatments are opening opportunities for efficient solutions in various industries. One of the most popular green vegetables, peas are members of the Fabaceae family and have a pod-like structure. Every year, a significant amount of pea pods is discarded as waste products of peas that have negative impacts on our environment. In this comprehensive review, we explore innovative methods for utilizing pea pods to minimize their environmental footprint and optimize their viability across multiple industries. A large portion of the pea processing industry's output consists of pea pods. Variety of proteins, with major classes being globulin and albumin (13%), dietary fiber (43-58%), and minerals are abundant in these pods. Because of their diverse physiochemical properties, they find applications in many diverse fields. The porous pea pods comprised cellulose (61.35%) and lignin (22.12%), which could make them superior adsorbents. The components of these byproducts possess valuable attributes that make them applicable across treatment of wastewater, production of biofuels, synthesis of biocolors, development of nutraceuticals, functional foods, and enzymes for the textile industry, modification of oil, and inhibition of steel corrosion.

Physical Treatments Modified the Functionality of Carrot Pomace.

This study addressed the critical issue of food waste, particularly focusing on carrot pomace, a by-product of carrot juice production, and its potential reutilization. Carrot pomace, characterized by high dietary fiber content, presents a sustainable opportunity to enhance the functional properties of food products. The effects of physical pretreatments-high shearing (HS), hydraulic pressing (HP), and their combination (HSHP)-alongside two drying methods (freeze-drying and dehydration) on the functional, chemical, and physical properties of carrot pomace were explored. The results indicated significant enhancements in water-holding capacity, fat-binding capacity, and swelling capacity, particularly with freeze-drying. Freeze-dried pomace retained up to 33% more carotenoids and demonstrated an increase of up to 22% in water-holding capacity compared to dehydrated samples. Freeze-dried pomace demonstrated an increase of up to 194% in fat-binding capacity compared to dehydrated samples. Furthermore, HSHP pretreatment notably increased the swelling capacity of both freeze-dried (54%) and dehydrated pomace (35%) compared to pomace without pretreatments. Freeze-drying can enhance the functional properties of dried carrot pomace and preserve more carotenoids. This presents an innovative way for vegetable juice processors to repurpose their processing by-products as functional food ingredients, which can help reduce food waste and improve the dietary fiber content and sustainability of food products.

Grains in a Modern Time: A Comprehensive Review of Compositions and Understanding Their Role in Type 2 Diabetes and Cancer.

Globally, type 2 diabetes (T2D) and Cancer are the major causes of morbidity and mortality worldwide and are considered to be two of the most significant public health concerns of the 21st century. Over the next two decades, the global burden is expected to increase by approximately 60%. Several observational studies as well as clinical trials have demonstrated the health benefits of consuming whole grains to lower the risk of several chronic non-communicable diseases including T2D and cancer. Cereals grains are the primary source of energy in the human diet. The most widely consumed pseudo cereals include (quinoa, amaranth, and buckwheat) and cereals (wheat, rice, and corn). From a nutritional perspective, both pseudo cereals and cereals are recognized for their complete protein, essential amino acids, dietary fibers, and phenolic acids. The bran layer of the seed contains the majority of these components. Greater intake of whole grains rather than refined grains has been consistently linked to a lower risk of T2D and cancer. Due to their superior nutritional compositions, whole grains make them a preferred choice over refined grains. The modulatory effects of whole grains on T2D and cancer are also likely to be influenced by several mechanisms; some of these effects may be direct while others involve altering the composition of gut microbiota, increasing the abundance of beneficial bacteria, and lowering harmful bacteria, increasing insulin sensitivity, lowering solubility of free bile acids, breaking protein down into peptides and amino acids, producing short-chain fatty acids (SCFAs), and other beneficial metabolites that promote the proliferation in the colon which modulate the antidiabetic and anticancer pathway. Thus, the present review had two aims. First, it summarized the recent knowledge about the nutritional composition and bioactive acids in pseudo cereals (quinoa, amaranth, and buckwheat) and cereals (wheat, rice, and corn); the second section summarized and discussed the progress in recent human studies, such as observational (cross-sectional studies, case-control studies, and cohort studies) and intervention studies to understand their role in T2D and cancer including the potential mechanism. Overall, according to the scientific data, whole grain consumption may reduce the incidence of T2D and cancer. Future studies should carry out randomized controlled trials to validate observational results and establish causality. In addition, the current manuscript encourages researchers to investigate the specific mechanisms by which whole grains exert their beneficial effects on health by examining the effects of different types of specific protein, dietary fibers, and phenolic acids that might help to prevent or treat T2D and cancer.

Dietary Fiber Intake and Clinical Outcomes in Chronic Kidney Disease: A Report From the Chronic Renal Insufficiency Cohort Study.

OBJECTIVE: Dietary interventions are the mainstay of chronic diseases prevention in general population, but the evidence to support such therapeutic approaches in patients with chronic kidney disease (CKD) is less robust. The objective of this study is to examine the association between dietary fiber intake and adverse cardiovascular and kidney outcomes and all-cause mortality in participants with CKD enrolled in the Chronic Renal Insufficiency Cohort study. DESIGN AND METHODS: A total of 3791 Chronic Renal Insufficiency Cohort participants with self-reported dietary fiber intake were included in the analyses stratified by tertiles of dietary fiber at study baseline. Hazard ratios for occurrence of all-cause mortality, composite cardiovascular events and composite kidney events were calculated using Cox Proportional Hazards models adjusted for demographic, clinical, and laboratory characteristics, including levels of inflammatory markers, C-reactive protein and interleukin-6. RESULTS: Mean daily dietary fiber intake was 15.2 g/day. During a median (standard deviation) follow up of 14.6 (4.4) years, 1074 deaths from any cause occurred. In multivariable adjusted models, participants in the middle and low dietary fiber tertiles had a 19% (hazard ratio [95% CI]), 1.19 [1.02, 1.39]) and 11% (1.11 [0.95, 1.31]) greater risk of death respectively, compared to those in the highest fiber intake tertile. No statistically significant associations were observed between dietary fiber intake and adverse cardiovascular and kidney outcomes. Higher dietary fiber intake was not significantly associated with lower levels of C-reactive protein and interleukin-6. CONCLUSION: A lower intake of dietary fiber was not associated with all-cause mortality in participants with CKD after adjustments for kidney function and inflammatory biomarkers. There was no significant association between dietary fiber intake and adverse kidney and cardiovascular outcomes. Future randomized intervention trials are needed to identify whether a high dietary fiber intake translates into improved clinical outcomes in CKD.

Association between serum uric acid levels and dietary fiber intake in adults: the Korea national health and nutrition examination survey (KNHANES VII, 2016-2018).

BACKGROUND: Hyperuricemia could be a risk for various chronic diseases, and it could be largely corrected by diet control. This study was a nationwide cross-sectional study to investigate the association between serum uric acid level and dietary fiber intake. METHODS: This study analyzed data based on the Korean National Health and Nutrition Examination Survey conducted from 2016 to 2018. Adults over 20 years of age with normal renal function, defined as an estimated glomerular filtration rate (eGFR) over 30mL/min/1.73m2, were included. The criteria for hyperuricemia were ≥ 7 mg/dL in men and ≥ 6 mg/dL in women. Data regarding dietary intake were obtained using the 24-hour recall method. RESULTS: A total of 15,278 subjects (6,455 males/8,823 females) were analyzed. The prevalence of hyperuricemia was 19.3% in men and 6.8% in women. There were significant, negative associations between serum uric acid and total fiber intake in both men and women. Consuming more than 27.9 g of dietary fiber in men and 20.7 g in women reduced the risk of hyperuricemia by approximately 30% with odds ratios of 0.72 (0.62-0.83) and 0.71 (0.56-0.88) in men and women, respectively. With regard to the risk reduction by the type of dietary fiber, cereal fiber was significantly identified in both men and women, while fruit fiber was only significant in men. In the subgroup analysis, this association remained significantly in young and metabolically healthy populations with normal weight. CONCLUSIONS: Dietary fiber intake was inversely associated with serum uric acid levels. This relationship was particularly significant in metabolically healthy young adults.

High-dietary fibers cereal bars containing malt bagasse by-product from the brewing industry.

The aim of this study was to use the malt bagasse by-product for developing high-dietary fibers cereal bars. Three formulations were tested and contained 0% (control), 19% and 24% of malt bagasse. The bars with malt bagasse were rich in dietary fiber and protein, with 6.06 and 26.35 g/100 g, respectively for samples with 19% of bagasse, and 8.43 and 26.22 g/100 g, respectively, for bars with 24% of this by-product. The total phenol content (TPC) of the bars with 19 and 24% of bagasse, was 100.37 and 192.13 mg GAE/100 g of sample, and the EC50 was 21.58 and 14.78 mg/mL (DPPH assay), respectively. The incorporation of this by-product into the formulations enhanced their TPC and antioxidant capacity. These samples had a high sensory acceptance. The formulation with the lowest malt bagasse concentration showed high global acceptance (56%) and purchase intention. The sensory attributes that pleased the tasters the most, rated as "liked moderately," were the color and odor of both bars. Cereal bars showed an improved nutritional composition and antioxidant capacity after malt bagasse addition, and the formulation with 19% should be the best choice among the tested formulations, when considering the set of nutritional and sensory aspects. The malt bagasse was successfully valorized as an ingredient in a functional food, whilst contributing to the environment.

Efficient arabinoxylan assay for wheat: Exploring variability and molecular marker associations in Wholemeal and refined flour.

In this study, we present a modified high throughput phloroglucinol colorimetric assay for the quantification of arabinoxylans (AX) in wheat named PentoQuant. The method was downscaled from a 10 ml glass tube to 2 ml microcentrifuge tube format, resulting in a fivefold increase in throughput while concurrently reducing the overall cost and manual labor required for the analysis. Comparison with established colorimetric assays and gas chromatography validates the modified protocol, demonstrating its superior repeatability, rapidity, and simplicity. The effectiveness of the protocol was tested on 606 unique whole meal (WM) and refined flour (RF) bread wheat samples which revealed the presence of more than a twofold variation in both the soluble (WE-AX) and total (TOT-AX) AX fractions in WM (TOT-AX = 31.9-76.1 mg/g; WE-AX = 4.4-12.6 mg/g) and RF (TOT-AX = 7.7-22.4 mg/g; WE-AX = 3.9-11.4 mg/g). Results obtained from the AX quantification were used to test the effectiveness of four molecular markers associated with AX variation and targeting two major genomic regions on the 1BL and 6BS chromosomes. These markers appeared to be particularly relevant for the WE-AX fraction, providing insights to enable marker-assisted breeding.

Dietary Fibers: Shaping Textural and Functional Properties of Processed Meats and Plant-Based Meat Alternatives.

The search for alternative sources of plant-based ingredients to improve the textural and sensory properties of plant-based meat alternatives (PMAs) is a growing trend, with the potential to enhance the sustainability of global food systems. While much focus has been placed on plant-based proteins, it is known today that dietary fibers (DFs) can also play a key role in the textural and other physicochemical properties of traditional processed meat products and PMAs. This review examined the latest scientific literature regarding the advantages of using DF in food. It showcases the latest applications of DF in processed meats, PMAs, and the effects of DF on the functional properties of food products, thereby aiming to increase DF applications to create improved, healthier, and more sustainable meat and PMA foods. The predominant effects of DF on PMAs and processed meats notably include enhanced gel strength, emulsion stability, improved water-holding capacity, and the formation of a uniform, porous microstructure. DF also commonly enhances textural properties like hardness, chewiness, springiness, and cohesiveness. While the impact of DF on processed meats mirrors that of PMAs, selecting the right DF source for specific applications requires considering factors such as chemical structure, solubility, size, concentration, processing conditions, and interactions with other components to achieve the desired outcomes.

Enzymatic degradation of pea fibers changes pea protein concentrate functionality.

Pea proteins are gaining increased interest from both the food industry as well as from consumers. Pea protein isolates (PPI) excel at forming meat-like textures upon heating while pea protein concentrates (PPC) are more challenging to transform into highly sought-after foods. PPCs are richer in dietary fibers (DF) and are more sustainable to produce than PPI. In this work, degradative enzymes were used to modify the functionality of PPC-water blends with a focus on texturization upon heating. Three enzyme solutions containing ß-glucanases, hemicellulases, pectinases, xylanase, and cellulases were added to 65 wt% PPC blends. The effect of these enzymatic pretreatments was measured by monitoring the torque in a mixing reactor during blending, differential scanning calorimetry (DSC), high-pressure shear rheology (HPSR), and DF content and size analysis. Four endothermic peaks were detected in the DSC thermograms of PPC, namely at 63 °C, 77 °C, 105 °C and 123 °C. The first three peaks were attributed to phase transition and gelation temperatures of the starches and proteins constituting PPC. No endothermic peaks were measured for PPI blends. Enzyme solutions containing ß-glucanases, hemicellulases, pectinases, and xylanases increased the endothermic energy of all peaks, hinting at an effect on the gelation properties of PPC. The same enzymes decreased the resistance to flow of PPC blends and induced a shift of the weight average molecular weight (Mw) distribution of soluble dietary fibers (SDF) towards smaller values while increasing the fraction of SDF by decreasing the insoluble dietary fiber (IDF) content. The solution containing cellulases did not change the DSC results or the viscosity of the PPC mixture, nor did it affect the IDF and SDF contents. On the other hand HPSR measurements of heated PPC samples up to 125 °C showed that all tested enzyme solutions decreased the complex viscosity of PPC-water blends to values similar to PPI-water blends. We demonstrated that degradative enzymes can enhance the functionality of less refined protein-rich ingredients based on pea and other vegetal sources. Using optimized enzyme blends for targeted applications can prove to be a key changer in the development and improvement of sustainable protein-rich foods.

Resident gut microbiota community determines the efficacy of soluble fiber in reducing adiposity.

Consumption of dietary fiber has been linked to several health benefits. Among these, dietary fiber breakdown through the process of anaerobic fermentation by the colonic microbiota leads to the production of beneficial metabolites, mainly short-chain fatty acids (acetate, propionate, and butyrate), which have been implicated in reduced calorie intake. Nevertheless, the link between gut microbiota and obesity remains unclear. We investigated the effects of dietary fibers on food intake and body weight gain in two independent but similarly designed studies in rats. In the first study, the inclusion of 10% w/w pectin, fructooligosaccharides or beta-glucan (n = 10/group) in the diets each significantly reduced body weight gain ('responders') compared to the cellulose control whereas, in a closely matched, but not fully identical study (n = 8/group), no effect of dietary fiber on body weight ('non-responders') was observed. The aim of this work was to explore the basis of this differential response between the two similarly designed and comparable studies, with a focus on the potential role of the gut microbiota in the control of food intake and body weight.

Comparative prebiotic potential of galacto- and fructo-oligosaccharides, native inulin, and acacia gum in Kenyan infant gut microbiota during iron supplementation.

Iron fortification to prevent anemia in African infants increases colonic iron levels, favoring the growth of enteropathogens. The use of prebiotics may be an effective strategy to reduce these detrimental effects. Using the African infant PolyFermS gut model, we compared the effect of the prebiotics short-chain galacto- with long-chain fructo-oligosaccharides (scGOS/lcFOS) and native inulin, and the emerging prebiotic acacia gum, a branched-polysaccharide-protein complex consisting of arabinose and galactose, during iron supplementation on four Kenyan infant gut microbiota. Iron supplementation did not alter the microbiota but promoted Clostridioides difficile in one microbiota. The prebiotic effect of scGOS/lcFOS and inulin was confirmed during iron supplementation in all investigated Kenyan infant gut microbiota, leading to higher abundance of bifidobacteria, increased production of acetate, propionate, and butyrate, and a significant shift in microbiota composition compared to non-supplemented microbiota. The abundance of the pathogens Clostridium difficile and Clostridium perfringens was also inhibited upon addition of the prebiotic fibers. Acacia gum had no effect on any of the microbiota. In conclusion, scGOS/lcFOS and inulin, but not acacia gum, showed a donor-independent strong prebiotic potential in Kenyan infant gut microbiota. This study demonstrates the relevance of comparing fibers in vitro prior to clinical studies.

UV-C Treatment Impact on the Availability of Water-Soluble Carbohydrates, Polyphenols, and Antioxidant Capacity of an Algerian Underutilized Date Fruit (Phoenix dactylifera L.).

Underutilized dates are considered as a socioeconomically important fruit for local and global communities, such as Degla-Beida, a common date fruit variety. The aim of this research was to elucidate, for the first time, the efficiency of UV-C light treatment (over different irradiation durations 5, 10, 20, and 40 min) in the enhancement of soluble carbohydrates and phenolic compounds, and to evaluate its effect on the antioxidant capacity. Furthermore, the content of dietary fiber was analyzed: insoluble dietary fiber (11.89 g/100 g); soluble dietary fiber (5.15 g/100 g); and total dietary fiber (17.06 g/100 g). The techno-functional properties were also determined: swelling capacity (3.94 mL/g); oil holding capacity (7.38 g/g); water holding capacity (9.30 g/g); and bulk density (1.81 g/mL). All were carried out to study the potential of exploiting this underutilized fruit for other applications as for feed or food. The results suggest that UV-C technology changes minimally the total water-soluble carbohydrate content; however, this preservation technology can affect the availability of different soluble carbohydrates depending on the irradiation time (IT), increasing the high molecular weight polysaccharides with IT up to 20 min, and some oligosaccharides with IT up to 5 min. The polyphenolic content determined by HPLC-QTOF was increased when the samples were submitted to UV-C reaching the maximum at 20 min (111.62 mg/100 g) and then to decrease in those submitted to IT of 40 min (12.05 mg/100 g). Regarding antioxidant capacity in the UV-C treated samples, FRAP decreased and EC50 on DPPH increased when IT was increased, while ORAC was hardly maintained. In addition, considering UV-C radiation associated with preservation and the studied date fruit as a rich source of dietary fiber with adequate techno-functional properties, this study presents valuable information for its potential use as a new food ingredient.