High Molecular Weight Carbohydrates Research Articles

Production and characterisation of protein isolates from Chilean granado beans (Phaseolus vulgaris L.)

SummaryGranado beans, widely cultivated in Chile, offer plant‐based proteins with functional benefits for healthier food formulations. These legumes have a 28% protein content (dry basis) with peptides called lectins that have the potential of reducing type‐II diabetes. Our lab has developed a membrane‐based method to produce protein isolates from oilseeds. This method was adapted for granado beans. The process involves alkaline extraction at pH 10, followed by ultrafiltration, diafiltration, acid precipitation at pH 4 and freeze‐drying. The resulting precipitated protein isolate contains 81% protein, comparable to other legumes. However, the acid‐soluble protein isolate (SPI) has a protein content of only 53% due to co‐recovery of high molecular weight carbohydrates. The total phenolic compound contents of the protein products were low resulting in both products having an attractive light colour with no astringent taste. The characterisation of the SPI by High‐Performance Liquid Chromatography found that it contained about 40% starch and other carbohydrates. To increase the protein content of SPI to ~90%, further purification steps to remove the carbohydrates are necessary.

Reinforcement of urea formaldehyde resins with pectins derived from orange peel residues for the production of wood-based panels

Pectin is a high molecular weight carbohydrate polymer that can be utilized in various applications in many sectors. The current study involved extracting pectin samples from orange peel residues and utilizing them as additives in water-based adhesive systems for producing composite wood panels. Three pectin types were used, named Pectin-A (extracted from orange peels with HCl), pectin-B (extracted from orange peels with H2SO4) and a commercial pectin called Pectin-C. The aim of the study was to examine the possibility of enhancing the efficacy of wood-based panels, such as particleboard, by strengthening amino resins like urea-formaldehyde resin (UF) using pectin samples. Three methods were utilized to incorporate the pectins into the adhesive systems: pectin 0.1% w/w dry/liquid resin added during the initial (1) and final (2) stage of the resin’s synthesis and pectin 0.1% w/w dry/liquid resin was incorporated into the glue mixture (3), which was then sprayed onto wood particles for the production of particleboard (PB) panels. It was found that pectins improve the performance of the final particleboards, especially when added during the UF resin synthesis. In addition, they may provide the adhesive and wood panel producers with a more environmentally friendly bio-additive for their products.

Microbial Exopolysaccharides: A Promising Health Booster

Microbial exopolysaccharides (EPS) are long-chain polysaccharides that are synthesized and secreted by microorganisms into the external matrix. In bacteria, EPS can either be associated with the cell surface in the form of capsules or be secreted into the environment. The yield of EPS is influenced by various factors, including the growth conditions and composition of the growth media. EPSs are high molecular-weight carbohydrates that consist of a backbone of repeated subunits of monosaccharides in varying ratios. Recently, there has been an increasing interest in EPS-producing microbes with Generally Recognized as Safe (GRAS) status. These food-grade organisms have the potential to produce polymers that can control the rheological and functional properties of food systems. EPSs have also been reported to have prebiotic and immune-modulating functions like anticancer, antidiabetic, antiviral, etc. The increasing recognition of the association between EPS and health benefits suggests the potential of EPS-producing starters with functional characteristics in the production of value-added functional products. Such products align with consumer demand for natural and healthy alternatives with fewer additives. The exploration of functional means of EPS in Pharmacology will provide an opportunity to identify novel and robust microbial resources producing unique EPSs.

Waste and their polysaccharides: Are they worth bioprocessing?

Environmental sustainability has gained serious concern worldwide due to rapid depletion of natural resources and simultaneous increase of carbon footprint. Disposing of waste biomass due to an ever-growing population has become a big issue imposing substantial environmental consequences. It is crucial to find an innovative solution to these challenges and high molecular weight (HMW) carbohydrate has proved to be one promising product. HMW carbohydrates obtained from waste biomass possess certain unique physicochemical properties which makes them optimal not only for environmental associated applications like wastewater treatment, bioremediation procedures, carbon sequestration processes but also suitable for commercial implementation. This paper gives an overview of the various sustainable energy alternatives, biopolymers and biocomposites obtained from carbohydrate waste biomasses highlighting their pros and cons. This study discusses the potential application of these in various industrial and commercial sectors along with environment associated aspects.

Isolation of Low Molecular Weight Carbohydrates from Seeds of SyzygiumCuminiandan Investigation into their Prebiotic Properties

Syzygium cumini(L.) Skeels (jamun) is a medically important fruit with numerous health protective effects. Seeds of this fruit contain 74.5 % NFE (nitrogen free extracts) and therefore possess a good source of carbohydrates. This fraction consists of high molecular weight carbohydrates (HMWC) like inulin (41.1 %) and resistant starch (3.9 mg/L); and hitherto unquantified low molecular weight carbohydrates (LMWC). This study was performed to extract and quantify LMWC from jamun seeds. To extract LMWC, ethanol concentration, extraction time and solute particle size were evaluated in 21 experimental designs using Response Surface Methodology (RSM) based on the central composite rotatable design (CCRD). A quadratic polynomial equation was obtained by multiple regression analysis. Analysis of variance (ANOVA) tested significance of the factors and their interactions at 95 % confidence interval. High Performance Anion Exchange Chromatography – Pulsed Amperometric Detection (HPAEC-PAD) was used to characterize the prebiotic fraction into individual sugars. Prebiotic potential of LMWC was established by calculating the Prebiotic Activity Score (PAS). A maximum LMWC yield (21 g / 100 g) was obtained when extraction was performed with 50 % ethanol as solvent for 80 to 85 h using the seed powder with 0.6 mm particle size. The predicted yield was in agreement with the experimental value and therefore proved the suitability of the RSM model. This model could be used as a standard for scaling up LMWC extraction from jamun seeds. A positive PAS of 1.532 ± 0.008 ascertained the prebiotic efficacy of the LMWC extracts. This score reflected the ability of probiotics like Lactobacillus acidophilus to gainfully utilize the LMWC in the growth medium in comparison to pathogenic strains like Escherichia coli.

Carbohydrate-Protein Interactions: Advances and Challenges.

A carbohydrate, also called saccharide in biochemistry, is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms. For example, sugars are low molecular-weight carbohydrates, and starches are high molecular-weight carbohydrates. Carbohydrates are the most abundant organic substances in nature and essential constituents of all living things. Protein-carbohydrate interactions play important roles in many biological processes, such as cell growth, differentiation, and aggregation. They also have broad applications in pharmaceutical drug design. In this review, we will summarize the characteristic features of protein-carbohydrate interactions and review the computational methods for structure prediction, energy calculations, and kinetic studies of protein-carbohydrate complexes. Finally, we will discuss the challenges in this field.

How can hydrothermal treatment impact the performance of continuous two-stage fermentation for hydrogen and methane co-generation?

Hydrothermal treatment can facilitate hydrolysis of biomass wastes such as algae and livestock manures, by converting high-molecular weight carbohydrates and proteins to monosaccharides and amino acids. However, further decomposition and reciprocal reaction of monosaccharides and amino acids are usually accompanied with hydrothermal treatment, which have negative impacts on microbial fermentation performance. In this study, glucose and glycine were used as model substrates during hydrothermal treatment coupled with semi-continuous hydrogen and methane fermentation. The results showed that thermal decomposition of glucose was stronger than glycine, due to the binary interactions between carbonyl group and amino group. Acidic condition could suppress conversion of intermediate compounds to polymers, thereby improving 5-HMF concentration to 7.59 g/L. Hydrothermal by-products had adverse impacts on hydrogen fermentation stability, resulting in a wide fluctuation of hydrogen production rate of around 0.55 L/L/d. Adding sulfuric acid for treatment would increase the competition of sulphate reducing bacteria, and cause a stuck methane fermentation. Additionally, by-products degradation promoted the growth of hydrogenotrophic and mixotrophic methanogens.

The Effects Of High Molecular Weight Carbohydrate Supplementation On Skeletal Muscle Performance

Athletes continue to seek new and improved strategies to preserve skeletal muscle strength and attenuate effects of skeletal muscle fatigue during resistance training. The ingestion of carbohydrates prior-to and during resistance training was hypothesized to improve both skeletal muscle performance and attenuate fatigue. VitargoS2TM is a high molecular weight carbohydrate supplement that promotes enhanced performance with its consumption prior-to and during physical activity. PURPOSE: To examine the influence of high molecular weight carbohydrate (HMC) consumption on skeletal muscle performance and fatigue following exhaustive lower-limb resistance training exercise. METHODS: Five-female and seven-male (n = 12) healthy college-aged individuals participated (26.1 ± 3.8 yrs) in a double-blinded crossover trial. Participants took part in three sessions across the study period: familiarization, Test Day 1 and Test Day 2. Participants were randomly assigned to one of two conditions [control (CON) or high molecular weight carbohydrate supplement (HMC)] for each of the two testing sessions. Lower-limb isometric and isokinetic concentric strength was assessed prior-to and immediately following a resistance-training session on two occasions. Outcome measures included lower-limb isometric and isokinetic concentric peak torque, blood glucose concentration, and rate of perceived exertion (RPE). RESULTS: The HMC condition elicited a significant increase in blood glucose concentration from Pre-Workout to Post-Workout (Pre-Workout: 92.1±14.4 mg/dl and Post-Workout: 118.3±15.2 mg/dl) compared to the control condition (Pre-Workout: 95.6±15.6 mg/dl and Post-Workout: 108.1±14.5 mg/dl). Isometric strength was reduced by 25.4 Nm (HMC) and 35.0 Nm (CON) following the lower-limb resistance training session; however, no ergogenic effect was found (p>0.05). Isokinetic concentric strength did not differ (p>0.05) following the HMC supplementation compared to the CON condition. No difference was found in RPE between the HMC and CON condition (p>0.05). CONCLUSIONS: The consumption of HMC supplementation prior to and during resistance-training exercise did not improve skeletal muscle performance and attenuated skeletal muscle fatigue following a lower-limb resistance-training exercise session.

Rehydration of food powders: Interplay between physical properties and process conditions

Dehydrated food powders with poor dissolution or dispersion can dramatically compromise food processing, with consequences for the final product quality and consumer experience. In this study, the reconstitution performance of maltodextrin powders with different moisture content and molecular weight, has been determined by varying the processing conditions, including agitation speed, liquid temperature, powder addition rate and mode of addition to the liquid surface.In particular, the inter-relationship between the glass transition temperature (Tg) of the powder, its moisture content and the liquid temperature (TL) is highlighted. When TL ≥ Tg, the individual maltodextrin granules tend to swell, restricting further dispersion and rehydration. It has been shown that higher liquid temperatures reduce the dispersion of food powders containing high molecular weight carbohydrates. Increasing the rate of powder addition to the liquid surface under low agitation conditions has been shown to result in faster reconstitution of low-molecular weight maltodextrins, whilst, on the other hand, the corresponding reconstitution rates of high-molecular weight maltodextrins are reduced.On the basis of this work and a previous study [X.Y. Ong, S.E. Taylor and M. Ramaioli, Pouring of Grains onto Liquid Surfaces: Dispersion or Lump Formation? Langmuir (2019) 1115011156] an improved, yet simple, approach to improve powder dispersion in a liquid is also demonstrated, by optimizing the distribution of the powder on the liquid surface. This approach avoids powder grains accumulating as heterogeneous lumps on the liquid surface and has been applied herein to a wide range of food powders.

Formulation and Evaluation of a Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum (Agaricomycetes), Nutraceutical Hydroalcoholic Suspension.

Ganoderma lucidum is a mushroom used in traditional Chinese medicine for its purported health benefits. Its complex chemical composition and potential synergies between bioactive compounds make it desirable to design a product that retains most of these compounds in a single formulation. In this article we evaluate a novel G. lucidum nutraceutical suspension (GNS) that reunites two fractions, an ethanolic extract and an aqueous extract, in a single oral liquid product. Back-to-back ethanolic and water extracts were mixed and the fraction that precipitates was recovered. The content of soluble solids, total triterpenoids, high molecular weight carbohydrates, and polyphenols was determined. A suspension was formulated by mixing the extracts and adding different concentrations of Carbomer® 940. The viscosity, physical stability, and particle size distribution were evaluated in all formulations. Almost 9% of the total extractives, consisting mostly of triterpenoids and phenolic compounds from the ethanolic extract, are insoluble in the hydroalcoholic mix and precipitate. This fraction can be suspended and kept stable with the aid of Carbomer® 940, a concentration between 0.5% and 1.0% showing adequate viscosity and particle size distribution. This preparation is an advantageous way of uniting the wide benefits of two G. lucidum extracts in a single oral liquid formulation.

Marine Carbohydrate-Based Compounds with Medicinal Properties.

The oceans harbor a great diversity of organisms, and have been recognized as an important source of new compounds with nutritional and therapeutic potential. Among these compounds, carbohydrate-based compounds are of particular interest because they exhibit numerous biological functions associated with their chemical diversity. This gives rise to new substances for the development of bioactive products. Many are the known applications of substances with glycosidic domains obtained from marine species. This review covers the structural properties and the current findings on the antioxidant, anti-inflammatory, anticoagulant, antitumor and antimicrobial activities of medium and high molecular-weight carbohydrates or glycosylated compounds extracted from various marine organisms.

The cell wall DUF642 At2g41800 (TEB) protein is involved in hypocotyl cell elongation

In plants, the cell wall is a complex and dynamic structure comprising high molecular weight carbohydrates and proteins. The cell wall plays an important role in several stages of the plant life cycle, including cell division, elongation and differentiation. The DUF642 family of cell wall proteins is highly conserved in spermatophytes and might be involved in pectin structural modifications. Particularly, At2g41800 is one of the most highly induced genes during the M/G1 phases of the cell cycle, and the protein encodes by this gene has been detected in cell wall proteomes of cell suspension cultures. In the present study, the expression of At2g41800 (TEB) was confirmed in primary and lateral roots, stigmatic papillae and hypocotyls. Subcellular localization studies showed that TEB is located in the cell wall. The root length and lateral root density were not affected in either of the two teb mutants studied, but the length of the hypocotyls from seedlings grown under light and dark conditions was increased. Immunogold labelling studies using JIM5 antibodies on sections of hypocotyl epidermal cells showed an important reduction of gold particles in teb mutants. The results suggested that TEB is involved in hypocotyl elongation.

Ingestion of High Molecular Weight Carbohydrate Enhances Subsequent Repeated Maximal Power: A Randomized Controlled Trial.

Athletes in sports demanding repeat maximal work outputs frequently train concurrently utilizing sequential bouts of intense endurance and resistance training sessions. On a daily basis, maximal work within subsequent bouts may be limited by muscle glycogen availability. Recently, the ingestion of a unique high molecular weight (HMW) carbohydrate was found to increase glycogen re-synthesis rate and enhance work output during subsequent endurance exercise, relative to low molecular weight (LMW) carbohydrate ingestion. The effect of the HMW carbohydrate, however, on the performance of intense resistance exercise following prolonged-intense endurance training is unknown. Sixteen resistance trained men (23±3 years; 176.7±9.8 cm; 88.2±8.6 kg) participated in a double-blind, placebo-controlled, randomized 3-way crossover design comprising a muscle-glycogen depleting cycling exercise followed by ingestion of placebo (PLA), or 1.2 g•kg•bw-1 of LMW or HMW carbohydrate solution (10%) with blood sampling for 2-h post-ingestion. Thereafter, participants performed 5 sets of 10 maximal explosive repetitions of back squat (75% of 1RM). Compared to PLA, ingestion of HMW (4.9%, 90%CI 3.8%, 5.9%) and LMW (1.9%, 90%CI 0.8%, 3.0%) carbohydrate solutions substantially increased power output during resistance exercise, with the 3.1% (90% CI 4.3, 2.0%) almost certain additional gain in power after HMW-LMW ingestion attributed to higher movement velocity after force kinematic analysis (HMW-LMW 2.5%, 90%CI 1.4, 3.7%). Both carbohydrate solutions increased post-exercise plasma glucose, glucoregulatory and gut hormones compared to PLA, but differences between carbohydrates were unclear; thus, the underlying mechanism remains to be elucidated. Ingestion of a HMW carbohydrate following prolonged intense endurance exercise provides superior benefits to movement velocity and power output during subsequent repeated maximal explosive resistance exercise. This study was registered with clinicaltrials.gov (NCT02778373).

Main Polysaccharides Isolated and Quantified of <i>Aloe vera</i> Gel in Different Seasons of the Year

We developed and implemented a methodology that allowed extracting and evaluating high molecular weight polysaccharides present in the gel of Aloe barbadensis Miller. One of the fractions evaluated revealed the presence of high molecular weight carbohydrates (200 kDa) with a behavior similar to that of acemannan and another fraction with compounds of molecular weights between 17 and 47 kDa. We quantified the concentration of acemannan for two different growing periods. The concentration of acemannan in the high molecular weight fraction was 99.97 ppm in the rainy season and 106.03 ppm in the dry season. The concentration of acemannan in the fraction of low molecular weight was 9.364 ppm during the season of greatest rainfall and 26.939 ppm in the dry season.

Effect of post-exercise ingestion of different molecular weight carbohydrate solutions. Part 1: The glucose and insulin response

Background Post-exercise ingestion of a high molecular weight (HMW) carbohydrate (CHO) solution has been shown to result in greater rates of muscle glycogen synthesis, attributed, in part, to the higher rates of gastric emptying compared to a low molecular weight (LMW) CHO solution. Given the higher rate of gastric emptying, a more rapid rise of glucose and insulin would be expected. However, differences have been reported in the pattern and time course of the subsequent insulin and glucose responses following ingestion. These differences have been attributed to timing and technique (venous vs. arterialized venous) of blood sampling. Thus, the current study sought to examine differences in the glucose, insulin, and glucagon response to postexercise ingestion of a HMW and LMW CHO solution.

Effect of post-exercise ingestion of different molecular weight carbohydrate solutions. Part II: The incretin response

Background Gastric inhibitory peptide (GIP) and glucagon like peptide-1 (GLP-1), incretin hormones of the small intestine, are secreted in response to the presence of food in the lumen. Once released into circulation, these incretins stimulate beta cells to increase insulin secretion, accounting for at least 50% of total insulin secreted after glucose ingestion. Post-exercise ingestion of a high molecular weight (HMW) carbohydrate (CHO) solution has been shown to result in greater rates of muscle glycogen synthesis, which are attributed to the higher rates of gastric emptying, compared to a low molecular weight (LMW) CHO solution. However, no studies have examined the effect of post-exercise ingestion of CHO’s of differing molecular weights on incretin response. Therefore, we sought to examine the difference in GIP and GLP-1 secretion after ingestion of HMW and LMW CHO solutions following a glycogen depleting exercise bout.

Effect of post-exercise ingestion of different molecular weight carbohydrate solutions. Part III: Power output during a subsequent resistance training bout

Background To maximize power adaptations, resistance training (RT) should be performed at maximal power output. In sports where more than one training bout is necessary in a day, subsequent RT may be limited by muscle glycogen, resulting in lower power output. High molecular weight (HMW) carbohydrate (CHO) solutions have been shown to result in greater glycogen re-synthesis rates, and greater work output during a subsequent cycling time trial compared to a low molecular weight (LMW) CHO solution. However, the effect of a HMW CHO on RT power output following exhaustive exercise is unknown.

ChemInform Abstract: Recent Developments of Ionic Liquids in Oligosaccharide Synthesis: The Sweet Side of Ionic Liquids.

The area of ionic liquid (IL) research has seen tremendous growth over the last few decades. The development of novel ILs with new and attractive physical and chemical properties has had a direct impact on organic synthesis. In particular, ILs have had many applications in carbohydrate chemistry including their use as solvents for dissolving high molecular weight carbohydrate polymers such as cellulose and as solvents and catalysts in oligosaccharide synthesis. In this area, ILs have been involved in protecting group manipulation reactions as well as glycosidic couplings leading to new methodologies and enhanced procedures. In addition, ILs have been successfully utilized as solution-phase purification supports. This review focuses on the most recent advances in the application of ILs to oligosaccharide synthesis. This is an emerging area that offers great promise at addressing some of the obstacles that remain on the path towards the automation of oligosaccharide synthesis.

Environmental and Gut Bacteroidetes: The Food Connection

Members of the diverse bacterial phylum Bacteroidetes have colonized virtually all types of habitats on Earth. They are among the major members of the microbiota of animals, especially in the gastrointestinal tract, can act as pathogens and are frequently found in soils, oceans and freshwater. In these contrasting ecological niches, Bacteroidetes are increasingly regarded as specialists for the degradation of high molecular weight organic matter, i.e., proteins and carbohydrates. This review presents the current knowledge on the role and mechanisms of polysaccharide degradation by Bacteroidetes in their respective habitats. The recent sequencing of Bacteroidetes genomes confirms the presence of numerous carbohydrate-active enzymes covering a large spectrum of substrates from plant, algal, and animal origin. Comparative genomics reveal specific Polysaccharide Utilization Loci shared between distantly related members of the phylum, either in environmental or gut-associated species. Moreover, Bacteroidetes genomes appear to be highly plastic and frequently reorganized through genetic rearrangements, gene duplications and lateral gene transfers (LGT), a feature that could have driven their adaptation to distinct ecological niches. Evidence is accumulating that the nature of the diet shapes the composition of the intestinal microbiota. We address the potential links between gut and environmental bacteria through food consumption. LGT can provide gut bacteria with original sets of utensils to degrade otherwise refractory substrates found in the diet. A more complete understanding of the genetic gateways between food-associated environmental species and intestinal microbial communities sheds new light on the origin and evolution of Bacteroidetes as animals’ symbionts. It also raises the question as to how the consumption of increasingly hygienic and processed food deprives our microbiota from useful environmental genes and possibly affects our health.

Effect of inorganic ions on bud cell formation by Fusarium oxysporum in potato dextrose broth

Potato dextrose broth (PDB), a well-known medium for cultivation of fungi, can be made from potato extract and glucose (handmade PDB) or bought as a commercial powder (commercial PDB). Previously, we reported that bud cell formation and fungal biomass of Fusarium oxysporum in handmade PDB are higher than in commercial PDB, and the presence of high molecular weight (>20 MDa) carbohydrates in PDB promoted bud cell formation by most strains of F. oxysporum. In this study, we report the effects of inorganic ions in PDB on bud cell formation and fungal biomass production by F. oxysporum. Concentrations of Mg, K, Fe, PO4 3− and SO4 2− were higher and of Na and Cl− were lower in handmade PDB than in commercial PDB. Adding each inorganic ion alone to commercial PDB showed that Mg is critical for enhancement of bud cell formation by some strains of F. oxysporum. The addition of Mg2+ with raw potato starch to commercial PDB promoted bud cell formation by some, but not all, of the seven F. oxysporum strains tested in this study.