Individual Fiber Components Research Articles

Challenges to Increasing Dietary Fiber in White Flour and Bread.

Increasing the intake of dietary fiber from staple foods is a key strategy to improve the health of consumers. White bread is an attractive vehicle to deliver increased fiber as it is widely consumed and available to all socio-economic groups. However, fiber only accounts for about 4% of the dry weight of white flour and bread compared to 10-15% in whole grain bread and flour. We therefore discuss the challenges and barriers to developing and exploiting new types of wheat with high fiber content in white flour. These include defining and quantifying individual fiber components and understanding how they are affected by genetic and environmental factors. Rapid high throughput assays suitable for determining fiber content during plant breeding and in grain-utilizing industries are urgently required, while the impact of fiber amount and composition on flour processing quality needs to be understood. Overcoming these challenges should have significant effects on human health.

The Influence of the Chemical Composition of Flax and Hemp Fibers on the Value of Surface Free Energy.

The article presents the exploration of flax and hemp fibers' surface free energy depending on the chemical composition of the fiber, which is closely related to the plant variety and the method of extracting the fiber. For this purpose, tests of the surface free energy (SFE), evaluation of the percentage content of individual fiber components and FTIR analyses were conducted. The research was carried out with the use of fibrous materials prepared in three different ways: 1. To analyze the effect of subsequent stages of flax fibers refining process on chemical composition and SFE, 2. to explore the dependence of fiber SFE on hemp variety, the water-retting hemp fibers were used, 3. To evaluate the influence of the retting method of hemp fibers BIAŁOBRZESKIE variety on SFE, the fibers extracted with the use of dew and water retting were used as the research material. The study confirmed that the content of individual components in the fiber influenced its sorption capacity and therefore determined its hydrophilic properties. The values of Pearson's linear correlation coefficients determined in the statistical analysis proved that the surface free energy was strongly correlated with the content of individual components in the fibers. Understanding the wettability characteristics of bast fibers will allow modeling the properties of products made of these fibers and designing surface modification processes in order to obtain specific functionality of textile products, depending on their intended utilization.

Components of the Fiber Diet in the Prevention and Treatment of IBD-An Update.

Inflammatory bowel disease (IBD) is a group of diseases with a chronic course, characterized by periods of exacerbation and remission. One of the elements that could potentially predispose to IBD is, among others, a low-fiber diet. Dietary fiber has many functions in the human body. One of the most important is its influence on the composition of the intestinal microflora. Intestinal dysbiosis, as well as chronic inflammation that occurs, are hallmarks of IBD. Individual components of dietary fiber, such as β-glucan, pectin, starch, inulin, fructooligosaccharides, or hemicellulose, can significantly affect preventive effects in IBD by modulating the composition of the intestinal microbiota or sealing the intestinal barrier, among other things. The main objective of the review is to provide information on the effects of individual fiber components of the diet on the risk of IBD, including, among other things, altering the composition of the intestinal microbiota.

Microstructural Alterations in Projection and Association Fibers in Neonatal Hypoxia-Ischemia.

Diffusion MRI (dMRI) is known to be sensitive to hypoxic-ischemic encephalopathy (HIE). However, existing dMRI studies used simple diffusion tensor metrics and focused only on a few selected cerebral regions, which cannot provide a comprehensive picture of microstructural injury. To systematically characterize the microstructural alterations in mild, moderate, and severe HIE neonates compared to healthy neonates with advanced dMRI using region of interest (ROI), tract, and fixel-based analyses. Prospective. A total of 42 neonates (24 males and 18 females). 3-T, diffusion-weighted echo-planar imaging. Fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), axial diffusivity (AD), fiber density (FD), fiber cross-section (FC), and fiber density and cross-section (FDC) were calculated in 40 ROIs and 6 tracts. Fixel-based analysis was performed to assess group differences in individual fiber components within a voxel (fixel). One-way analysis of covariance (ANCOVA) to compare dMRI metrics among severe/moderate/mild HIE and control groups and general linear model for fixel-wise group differences (age, sex, and body weight as covariates). Adjusted P value < 0.05 was considered statistically significant. For severe HIE, ROI-based analysis revealed widespread regions, including the deep nuclei and white matter with reduced FA, while in moderate injury, only FC was decreased around the posterior watershed zones. Tract-based analysis demonstrated significantly reduced FA, FD, and FC in the right inferior fronto-occipital fasciculus (IFOF), right inferior longitudinal fasciculus (ILF), and splenium of corpus callosum (SCC) in moderate HIE, and in right IFOF and left anterior thalamic radiation (ATR) in mild HIE. Correspondingly, we found altered fixels in the right middle-posterior IFOF and ILF, and in the central-to-right part of SCC in moderate HIE. For severe HIE, extensive microstructural injury was identified. For moderate-mild HIE, association fiber injury in posterior watershed area with a rightward lateralization was found. 1 TECHNICAL EFFICACY: Stage 3.

Influence of fibre cross-sectional shape on air permeability of nonwovens

In this work, a series of needle-punched nonwoven fabrics was prepared by mixing polyester fibres of circular and deep-grooved cross-sections at different mass proportions and evaluated for their mean fibre shape, pore diameter and air flow behaviour. A simple and easy-to-use expression was developed for prediction of mean fibre shape in nonwoven fabrics prepared by mixing of fibres of different cross-sections. The mean fibre shape factor was found to be a weighted arithmetic mean of the shape factors of individual fibre components, where the weightage was determined by the product of volume and fineness fractions of individual fibre components. The nonwoven fabric prepared by circular fibres alone displayed the highest pore diameter, while the nonwoven fabric prepared by deep-grooved fibres alone exhibited the lowest pore diameter. The pore diameter was found to increase non-linearly with an increase in mass proportion of circular fibres in the nonwoven fabrics. The relationship between fibre shape and pore diameter was theoretically derived and experimentally verified. The air flow behaviour of nonwoven fabrics was found to be explained by Darcy’s law reasonably well. The nonwoven fabric prepared by circular fibres alone exhibited the highest air permeability, while the nonwoven fabric prepared by deep-grooved fibres alone displayed the lowest air permeability. The air permeability was found to decrease with a higher proportion of non-circular fibres in the nonwoven fabrics. This behaviour could not be explained reasonably well by Hagen-Poiseuille’s equation, however. But when the Reynolds number and the friction factor were taken into account, the predicted results were found in close agreement with the experimental ones.

&lt;i&gt;Claviceps cyperi&lt;/i&gt;, a new cause of severe ergotism in dairy cattle consuming maize silage and teff hay contaminated with ergotised &lt;i&gt;Cyperus esculentus&lt;/i&gt; (nut sedge) on the Highveld of South Africa

During December/January 1996/97 typical summer syndrome (hyperthermia and a 30% drop in milk yield) occurred in succession in two Holstein dairy herds (n=240 and n=150 milking cows, respectively) on the South African Highveld. These farms are situated in the midst of the prime maize and dairy farming areas of South Africa where this condition had never been diagnosed before. The individual components of the concentrate on both farms were negative for ergot alkaloids. Endophytic fungi and/or ergot infestation of teff and other grasses fed to the cows were then suspected of being involved, but neither endophytes nor ergot alkaloids could be implicated from these sources. By measuring the serum prolactin levels of groups of sheep (n=5) fed the first farm's total mixed ration (TMR) or its three individual fibre components for a period of 11 days, the source of the ergot alkaloids was identified. A statistically significant decrease in the level of this hormone occurred only in the group on maize silage (which constituted 28% on dry matter base of the TMR). The involvement of the maize silage was further chemically confirmed by the high levels of total ergot alkaloids, predominantly ergocryptine, found by LC-MS in the silage as well as in the TMR (115-975 ppb and 65-300 ppb, respectively). The ergot alkaloid content (mainly ergocryptine) of the maize silage on the second affected farm was 875 ppb. Withdrawal of contaminated silage resulted in gradual recovery of stock on both farms. Nut sedge (Cyperus esculentus and Cyperus rotundus of the family Cyperaceae) has a world-wide distribution and is a common weed in annual crops, and can be parasitized by Claviceps cyperi. Careful examination of the maize silage from both farms revealed that it was heavily contaminated with nut sedge and that it contained minute sclerotia, identified as those of Claviceps cyperi, originating from the latter. Nut sedge was abundant on both farms and it is believed that late seasonal rain had resulted in mature, heavily ergotised nut sedge being cut with the silage. Claviceps cyperi sclerotia, collected on the affected fields in the following autumn contained 3600-4000 ppm ergocryptine. That the dominant alkaloid produced by this particular fungus was indeed ergocryptine, was confirmed by negative ion chemical ionization MS/MS. In one further outbreak in another Holstein herd, teff hay contaminated with ergotised nut sedge and containing 1200 ppb alkaloids, was incriminated as the cause of the condition. This is the first report of bovine ergotism not associated with the Poaceae infected with Claviceps purpureum or endophytes but with the family Cyperaceae and this particular fungal phytopathogen.

Binding of Zinc to Apple Fiber, Wheat Bran, and Fiber Components

ABSTRACTZinc ion binding to commercial brans, fiber, and fiber components was studied by equilibrium dialysis. Maximum initial concentration of zinc bound by 50 ma of apple fiber (AF) and wheat bran (WB) at pH 7.2 was 220 μg. AF and WB binding capacities were significantly lower for soluble fractions than for unfractionated materials. The water‐soluble fraction's binding capacity was 90% lower for AF than for WB. Hemicellulase and phytase slightly increased AF binding capacity but reduced WB capacity. Pectinase increased both AF and WB capacity slightly. Binding capacities of commercially available individual fiber components decreased in the order: lignin &gt; polypectin &gt; pectin &gt; gum &gt; cellulose. Zinc‐binding capacities of various dietary fiber types differ, accounting for different zinc bioavailabilties of some foods.

Isolated Fiber Components and pH Alter Methylazoxymethanol Acetate Mutagenicity

Dietary fibers, 300 ug of pectin, lignin, hemicellulose, or cellulose, were preincubated with either 1500 uM, 1000 uM, 750 uM, or 500 uM of the mutagen methylzoxymethanol acetate (MAM acetate) at pH 5.4,2.1, and 6.6 simulating gastrointestinal conditions. A modification of the Ames assay was used with Salmonella typhimurium his G46 and no S-9 activation to determine any change in mutagenic activity of MAM acetate with and without the individual fiber components at each pH level.AtpH 5.4 MAM acetate was only weakly mutagenic, therefore it was difficult to assess the effect of the fiber components. MAM acetate displayed the highest level of mutagenicity at pH 2.1. At pH 2.1 the percent inhibition of MAM acetate induced revertants with pectin and hemicellulose was greater than 99%. Lignin caused 91% inhibition, but cellulose did not effectively inhibit mutagenicity. At pH 6.6 MAM acetate was mutagenic only with 1500 uM and 1000 uM concentrations. At pH 6.6 lignin and hemicellulose caused 99% inhibition, pectin 97%, and cellulose 38%. The results indicate that the effect of dietary fiber on mutagenicity is dependent on the specific fiber component tested, and support the theory that inhibition of mutagenicity is due to binding of the mutagen with the fiber component.

Decomposition of aquatic angiosperms. II. Particulate components

The decomposition of particulate organic matter (POM) from five species of freshwater vascular macrophytes was analyzed over a 180-day period under controlled conditions of temperature and oxygen (10 and 25°C; aerobic and anaerobic). In addition, a series of seasonal decomposition experiments were conducted in situ under different lake conditions. Plant species studied included the emergent Scirpus acutus Bigelow, the floating-leaved lily Nuphar variegatum Engelm., and the submersed Myriophyllum heterophyllum Michx., Najas flexilis (Willd.) Rostk. & Schmidt, and the submersed bulrush Scirpus subterminalis Torrey. At 2, 4, 10, 24, 48, 90, and 180-day intervals, organic weight, ash, carbon, nitrogen, total non-structural carbohydrates (TNC), and fiber components (lignin, cellulose, and hemicellulose) were determined under each of the experimental conditions. A model was developed that fit the observed weight-loss data, which demonstrated that decay-rate coefficients decreased exponentially with time in response to increasing resistance to decomposition of residual organic constituents. The fastest decomposing species, Nuphar, exhibited losses from 60 (cold, anaerobic) to 90% (warm, aerobic) over a 180-day period; the slowest, Scirpus acutus, lost only 20 and 40% under comparable conditions. TNC content decreased more rapidly under warm aerobic than under cold anaerobic conditions. Reduction of TNC was greatest in Nuphar, less in Myriophyllum and Najas, and lowest in the two Scirpus species. Structural carbohydrates decreased slowly among all species with the lignin fraction being the most resistant to degradation. However, decay rates of the macrophytes were negatively correlated to total fiber content rather than to individual fiber components (hemicellulose, cellulose, and lignin). Floating-leaved plants contained the least amount of structural tissue and decayed most rapidly, followed by submersed and then emergent species. Scirpus subterminalis, although submersed, retains the structural characteristics of the emergent species of this genus and decayed in much the same way as S. acutus. The C:N ratios of tissue of Scirpus acutus were higher than for other species and continuously declined during decomposition under warm, aerobic conditions. In this species, the C:N ratios decreased very slowly under cold, anaerobic conditions. The C:N ratios of the other species were constant after initial rapid declines. Among all species, the proportion of nitrogen in the dissolved organic and inorganic matter of the media decreased rapidly to low levels during decomposition at both low and high temperatures under anaerobic conditions; reductions were less when oxygen was available and decreased least in cultures of the two Scirpus species. Thus, resistance of particulate tissue to microbial decomposition was strongly influenced by the composition of the plant species. The floating-leaved plant decomposed faster than the submersed plants, which decomposed more rapidly than the emergent species. Decay rates were related to initial nitrogen and fiber contents, with high-nitrogen, low-fiber plants decomposing most rapidly. Unlike the leached dissolved organic matter (DOM) of the plants whose rate of decomposition was found to be mostly influenced by oxygen availability, the rate of conversion of particulate matter to carbon dioxide and/or DOM was regulated primarily by temperature, tissue nitrogen, and fiber content. All species showed similar trends in decomposition under both laboratory and in situ conditions, but the species-specific rates differed under the various laboratory conditions of temperature and oxygen.