Search Results (14)

Barley, rich in beneficial ingredients, has been recognised as a healthy food and is widely used in the production of healthy foods for humans. The current study identified a new barley mutant with the SSIIa, SSIIIa, SBEIIa, and SBEIIb genes inactivated in the genome-edited offspring of targeted mutagenesis of starch synthetic genes using multiplex genome editing. The grain compositions and starch properties of the ssIIa/ssIIIa/sbeIIa/sbeIIb mutant were analysed and compared with the corresponding parameters of ssIIa, ssIIIa, sbeIIa/sbeIIb, ssIIa/sbeIIa/sbeIIb, and non-genome-edited lines (NE), respectively. ssIIa/ssIIIa/sbeIIa/sbeIIb exhibited the highest contents of β-glucan and amylose content among all mutants and NE, but not the most prominent in resistant starch, fructan, and fibre contents. The loss of SSIIa, SSIIIa, SBEIIa, and SBEIIb genes also resulted in significant changes in starch properties. This study enriched the genotypes of healthy barley and provided a theoretical basis for improving barley quality. Full article

The gut microbiota, a complex ecosystem of microorganisms in the human gastrointestinal tract (GI), plays a crucial role in maintaining metabolic health and influencing disease susceptibility. Dysbiosis, or an imbalance in gut microbiota, has been linked to the development of type 2 diabetes mellitus (T2DM) through mechanisms such as reduced glucose tolerance and increased insulin resistance. A balanced gut microbiota, or eubiosis, is associated with improved glucose metabolism and insulin sensitivity, potentially reducing the risk of diabetes-related complications. Various strategies, including the use of prebiotics like inulin, fructooligosaccharides, galactooligosaccharides, resistant starch, pectic oligosaccharides, polyphenols, β-glucan, and Dendrobium officinale have been shown to improve gut microbial composition and support glycemic control in T2DM patients. These prebiotics can directly impact blood sugar levels while promoting the growth of beneficial bacteria, thus enhancing glycemic control. Studies have shown that T2DM patients often exhibit a decrease in beneficial butyrate-producing bacteria, like Roseburia and Faecalibacterium, and an increase in harmful bacteria, such as Escherichia and Prevotella. This review aims to explore the effects of different prebiotics on T2DM, their impact on gut microbiota composition, and the potential for personalized dietary interventions to optimize diabetes management and improve overall health outcomes. Full article

β-glucans found in cereal grains have been previously demonstrated to improve blood glucose control; however, current understanding points to their high viscosity as the primary mechanism of action. In this work, we present a novel, highly soluble, low-viscosity β-glucan fiber (HS-BG fiber) and a preclinical dataset that demonstrates its impact on two mechanisms related to the prevention of hyperglycemia. Our results show that HS-BG inhibits the activity of two key proteins involved in glucose metabolism, the α-glucosidase enzyme and the SGLT1 transporter, thereby having the potential to slow starch digestion and subsequent glucose uptake. Furthermore, we demonstrate in a multi-donor fecal fermentation model that HS-BG is metabolized by several different members of the gut microbiome, producing high amounts of short-chain fatty acids (SCFAs), known agonists of GPR43 receptors in the gut related to GLP-1 secretion. The production of SCFAs was verified in the translational gut model, SHIME^®. Moreover, HS-BG fiber fermentation produces compounds that restored permeability in disrupted epithelial cells, decreased inflammatory chemokines (CXCL10, MCP-1, and IL-8), and increased anti-inflammatory marker (IL-10), which could improve insulin resistance. Together, these data suggest that the novel HS-BG fiber is a promising new functional ingredient that can be used to modulate postprandial glycemic responses while the high solubility and low viscosity enable easy formulation in both beverage and solid food matrices. Full article

The aim of this work was to develop sustainable patches for wound application, using the biopolymer starch, created using a low-cost 3D printing PAM device. The composition of a starch gel was optimized for PAM extrusion: corn starch 10% w/w, β-glucan water suspension (filler, 1% w/w), glycerol (plasticizer, 29% w/w), and water 60% w/w. The most suitable 3D printing parameters were optimized as well (nozzle size 0.8 mm, layer height 0.2 mm, infill 100%, volumetric flow rate 3.02 mm³/s, and print speed 15 mm/s). The suitable conditions for post-printing drying were set at 37 °C for 24 h. The obtained patch was homogenous but with low mechanical resistance. To solve this problem, the starch gel was extruded over an alginate support, which, after drying, becomes an integral part of the product, constituting the backing layer of the final formulation. This approach significantly improved the physicochemical and post-printing properties of the final bilayer patch, showing suitable mechanical properties such as elastic modulus (3.80 ± 0.82 MPa), strength (0.92 ± 0.08 MPa), and deformation at break (50 ± 1%). The obtained results suggest the possibility of low-cost production of patches for wound treatment by additive manufacturing technology. Full article

Indigestible glucans (IGs) are dietary fibers that can promote human health via fermentation by the gut microbiota, where their physico-chemical properties play a crucial role. This effect remains to be fully explored. The aim of the current study was to comprehensively investigate and compare the fermentation characteristics of IGs with various structural properties, as well as their effects on the gut microbiota. Barley β-glucan (BG), laminarin (L), yeast β-glucan (BY), pachyman (PAC), resistant starch (R), and litesse (Lit) were anaerobically batch-fermented using the human fecal microbiota for 48 h. All the IGs were utilized by the gut microbiota at different rates, and 2% of L, 14% of BG, 23% of BY and PAC, and 35% of R and Lit were unfermented at the 48^th hour. During fermentation, mono-, di-, or trisaccharides were released from BG, L, and Lit, and the pH of broth was greatly lowered by IGs, especially BG and L, along with the production of short-chain fatty acids. Interestingly, PAC favored butyric acid production, while BG, L, and BY preferred propionic acid. Moreover, lactic acid, but not succinic acid, was detected in considerable amounts, but only with BG and L after 5 h. 16S rDNA analysis showed different microbial structures and the selective promotion of bacteria with different IGs, while only PAC did not decrease microbial α-diversity. Further qPCR analysis confirmed that BG was more potent at proliferating Faecalibacterium prausnitzii; BY preferred total bacteria, Prevotella, and Lactobacillus; and R favored Bifidobacterium. The IG-induced changes in the gut microbiota were strongly correlated with carboxylic acid production. In conclusion, the six IGs differed in fermentation characteristics and gut microbiota regulation capacity, and each one could have specific applications in human health promotion. Full article

The properties of each food, composition, and structure affect the digestion and absorption of nutrients. Dietary fiber (DF), especially viscous DF, can contribute to a reduction in the glycemic response resulting from the consumption of carbohydrate-rich foods. Target and control of postprandial glycemic values are critical for diabetes prevention and management. Some mechanisms have been described for soluble DF action, from the increase in chyme viscosity to the production of short-chain fatty acids resulting from fermentation, which stimulates gastrointestinal motility and the release of GLP-1 and PYY hormones. The postprandial glycemic response due to inulin and resistant starch ingestion is well established. However, other soluble dietary fibers (SDF) can also contribute to glycemic control, such as gums, β-glucan, psyllium, arabinoxylan, soluble corn fiber, resistant maltodextrin, glucomannan, and edible fungi, which can be added alone or together in different products, such as bread, beverages, soups, biscuits, and others. However, there are technological challenges to be overcome, despite the benefits provided by the SDF, as it is necessary to consider the palatability and maintenance of their proprieties during production processes. Studies that evaluate the effect of full meals with enriched SDF on postprandial glycemic responses should be encouraged, as this would contribute to the recommendation of viable dietary options and sustainable health goals. Full article

Resistant starch (RS) is a special group of starches which are slowly degraded and rarely digested in the gastrointestinal tract. It was recognized as a new type of dietary fiber that improved cardiovascular, cerebrovascular, and intestinal health. Breeding high-RS-content wheat is one of the most efficient and convenient approaches for providing an adequate amount of RS for a healthy diet. However, studies which aim to genetically illustrate RS content in wheat are still rare. In the present study, a panel of 207 wheat varieties were collected world-wide and planted under three locations. The RS content of each variety was measured, and 14 additive genetic loci were found to stably exist under more than two environments. Meanwhile, four genes were recognized as the putative candidates with annotated functions of β-amylase, α-1,4 glucan phosphorylase, sucrose transporter, and NAC domain protein. A kompetitive allele-specific PCR (KASP) marker was developed from the SNP AX-94546744, representing the genetic locus of β-amylase located. The AX-94546744-T allele can significantly increase the RS content compared to the AX-94546744-C allele. The genetic loci and KASP marker associated with RS content may be useful for wheat germplasm cultivation and variety breeding with a high RS content, further helping to improve the nutritional quality in wheat. Full article

Dietary fiber exerts beneficial effects on human health reducing the risk factors of metabolic related diseases such as hyperglycemia, insulin resistance, and hypercholesterolemia. The aim of this study is to demonstrate the efficacy of a food supplement based on brewer’s spent grain (BSG) extract in the reduction of postprandial glycemia and insulinemia in normoglycemic subjects. BSG was chemically characterized, revealing the presence of resistant starch (14.64 g/100 g), arabinoxylans (7.50 g/100 g), β-glucans (1.92 g/100 g) and other soluble fibers (6.43 g/100 g), and bioaccessible ferulic acid (91.3 mg/100 g). For the clinical study, 40 normoglycemic subjects were randomized into two groups, 1 and 2 (n = 20), for a cross-over clinical design and received either BSG extract-based food supplement or placebo. Postprandial blood glucose values were significantly lower than corresponding values in the placebo group after 90 and 120 min, while at the baseline and in the first 60 min, the two glycemic curves overlapped substantially. This improved clinical outcome was corroborated by significant reductions in postprandial insulinemia. None of the subjects reported adverse effects. This study showed that the tested BSG extract-based food supplement improves glucose metabolism and insulinemic response in normoglycemic subjects with at most a mild insulin resistance. Full article

To investigate the effect of oat bran on bread quality and the mechanism of reducing the glycemic index (GI) of bread, wheat bran (10%, w/w, flour basis), oat bran (10%), and β-glucan (0.858%) were individually added to determine the expansion of dough, the specific volume, texture, color, GI, starch digestion characteristics, and α-amylase inhibition rate of bread. The results showed that the incorporation of wheat bran and oat bran both reduced the final expanded volume of the dough, decreased the specific volume of the bread, and increased the bread hardness and crumb redness and greenness values as compared to the control wheat group. The above physical properties of bran-containing bread obviously deteriorated while the bread with β-glucan did not change significantly (p < 0.05). The GI in vitro of bread was in the following order: control (94.40) > wheat bran (69.24) > β-glucan (65.76) > oat bran (64.93). Correspondingly, the oat bran group had the highest content of slowly digestible starch (SDS), the β-glucan group had the highest content of resistant starch (RS), and the control group had the highest content of rapidly digestible starch (RDS). For the wheat bran, oat bran, and β-glucan group, their inhibition rates of α-amylase were 9.25%, 28.93%, and 23.7%, respectively. The β-glucan reduced the bread GI and α-amylase activity by intertwining with starch to form a more stable gel network structure, which reduced the contact area between amylase and starch. Therefore, β-glucan in oat bran might be a key component for reducing the GI of whole oat bread. Full article

One type of functional food that has been receiving much attention is food rich in prebiotics. The old but still valid definition of prebiotics defines them as non-digestible food components that selectively stimulate the growth and/or activity of the beneficial bacteria in the colon and, as a result, improve the host health. Cereals, as one of the main components in the human diet, contain substantial levels of dietary fiber with probable prebiotic potential. In addition, dietary fiber, particularly soluble dietary fiber, has recently emerged as a promising natural highly functional food ingredient in food production. This review focuses on the prebiotic potential of cereal dietary fiber types and covers the achievements and developments regarding its isolation. First, the probiotic and prebiotic concepts will be discussed. Next, different components of dietary fiber and their effect on the host bacteria through in vitro and/or in vivo studies will be reviewed. In a last part, this paper also discusses means of boosting the prebiotic properties of cereal components and innovative strategies for the extraction of cereal dietary fiber. The review focuses on wheat as a leading cereal crop that is widely and intensely used throughout the world in food production. Full article

Wheat bran (WB) is rich in insoluble arabinoxylan, while BARLEYmax (BM) is a barley line that is rich in fructan, resistant starch, and β-glucan. In the present study, we investigated which of these two fiber sources would produce more favorable changes in the fecal variables of healthy subjects. Sixty healthy subjects were randomly divided into four groups (n = 15 per group) and fed twice daily for 4 weeks with baked cereal bars containing neither WB nor BM (WB−BM−), WB without BM (WB+BM−), BM without WB (WB−BM+), or WB and BM (WB+BM+). At baseline and after 4 weeks, the fecal microbiota composition and the concentrations of short-chain fatty acids were measured. A significant interactive effect of WB and BM on the abundance of genus Bacteroides was observed at week 4. The abundance of butyrate-producing bacteria and the fecal concentration of n-butyrate were significantly higher in the WB+ groups than in the WB− groups. In conclusion, WB was associated with elevated fecal concentrations of short-chain fatty acids including butyrate owing to an increase in the abundance of butyrate-producing bacteria. Additionally, the combination of WB and BM was associated with an increase in the abundance of genus Bacteroides. Therefore, both WB alone and WB combined with BM favorably influenced the fecal variables of healthy subjects. Full article

Numerous studies reveal the cardiovascular benefits of consuming dietary fiber and, especially, cereal fiber. Cereal fiber is associated with cardiovascular risk reduction through multiple mechanisms and consuming a variety of cereal fiber sources offers health benefits specific to the source. Certain cereal fibers have been studied more extensively than others and provide greater support for their incorporation into a healthful diet. β-glucan from oats or barley, or a combination of whole oats and barley, and soluble fiber from psyllium reduces the risk of coronary heart disease; inulin-type fructans added to foods and beverages may modestly decrease serum triacylglycerols; arabinoxylan and resistant starch may improve glycemic control. Individuals with low cereal fiber intake should increase their intake of whole grains in order to receive the benefits of whole grains in addition to fiber. For those adjusting to the texture and palatability of whole grains, turning to added-fiber products rich in β-glucan and psyllium may allow them to reach their fiber goals without increasing caloric intake. Full article

Extractable dietary fiber (DF) plays an important role in nutrition. This study on porridge making with whole grain rye investigated the effect of rest time of flour slurries at room temperature before cooking and amount of flour and salt in the recipe on the content of DF components and molecular weight distribution of extractable fructan, mixed linkage (1→3)(1→4)-β-D-glucan (β-glucan) and arabinoxylan (AX) in the porridge. The content of total DF was increased (from about 20% to 23% of dry matter) during porridge making due to formation of insoluble resistant starch. A small but significant increase in the extractability of β-glucan (P = 0.016) and AX (P = 0.002) due to rest time was also noted. The molecular weight of extractable fructan and AX remained stable during porridge making. However, incubation of the rye flour slurries at increased temperature resulted in a significant decrease in extractable AX molecular weight. The molecular weight of extractable β-glucan decreased greatly during a rest time before cooking, most likely by the action of endogenous enzymes. The amount of salt and flour used in the recipe had small but significant effects on the molecular weight of β-glucan. These results show that whole grain rye porridge made without a rest time before cooking contains extractable DF components maintaining high molecular weights. High molecular weight is most likely of nutritional importance. Full article

Dietary fiber and whole grains contain a unique blend of bioactive components including resistant starches, vitamins, minerals, phytochemicals and antioxidants. As a result, research regarding their potential health benefits has received considerable attention in the last several decades. Epidemiological and clinical studies demonstrate that intake of dietary fiber and whole grain is inversely related to obesity, type two diabetes, cancer and cardiovascular disease (CVD). Defining dietary fiber is a divergent process and is dependent on both nutrition and analytical concepts. The most common and accepted definition is based on nutritional physiology. Generally speaking, dietary fiber is the edible parts of plants, or similar carbohydrates, that are resistant to digestion and absorption in the small intestine. Dietary fiber can be separated into many different fractions. Recent research has begun to isolate these components and determine if increasing their levels in a diet is beneficial to human health. These fractions include arabinoxylan, inulin, pectin, bran, cellulose, β-glucan and resistant starch. The study of these components may give us a better understanding of how and why dietary fiber may decrease the risk for certain diseases. The mechanisms behind the reported effects of dietary fiber on metabolic health are not well established. It is speculated to be a result of changes in intestinal viscosity, nutrient absorption, rate of passage, production of short chain fatty acids and production of gut hormones. Given the inconsistencies reported between studies this review will examine the most up to date data concerning dietary fiber and its effects on metabolic health. Full article