Viscoelastic properties of oat β-glucan-rich aqueous dispersions

Highly Soluble β-Glucan Fiber Modulates Mechanisms of Blood Glucose Regulation and Intestinal Permeability

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.

Evernia prunastri lichen as a source of bioactive glucans with potential for topical applications

Microwave hydrothermal treatment was selected to extract valuable fractions with bioactive and gelling properties from Evernia prunastri lichen with potential for topical applications. The impact of the extraction processing conditions on the soluble extracts, mucilage fraction and residual solid phase was analyzed within a lichen global valorization approach. A particular stress was made on the thermo-rheological and structural characteristics of the extracted glucan and galactomannan polymers, the corresponding gelled matrices, and their cosmetic feasibility. Results revealed that the proposed microwave-assisted treatment showed a relevant influence on the phytochemical features of the aqueous soluble extracts, accounting the major protein content at 120 °C and the enhanced antioxidant and anti-tyrosinase properties at 140 °C. Extracts at 200 °C showed the highest anti-inflammatory (COX-1 and COX-2 inhibition) efficacies. The biopolymer analyses indicated that those recovered after lichen hydrothermal treatment at 160 °C featured a good extraction performance, the highest molecular weight, apparent viscosity, and antiproliferative potential. The thermo-rheological properties of the corresponding matrices formulated at 10 % and 60 or 80 °C exhibited the strongest and most thermo-reversible characteristics, as well as antifreezing feasibility. Another advantage of the selected fractions was the absence of skin irritation according to the in vitro skin irritation assay.

Effects of L.plantarum dy-1 fermentation time on the characteristic structure and antioxidant activity of barley β-glucan in vitro

This article explored the effect of Lactobacillus plantarum dy-1 (L. plantarum dy-1) fermentation on the basic physicochemical properties and associated in vitro antioxidant activity of barley β-glucan, including its molecular weight, monosaccharide composition, characteristic structure and rheology. Its DPPH, ABTS, hydroxyl radical scavenging capacity, and ferric reducing antioxidant potential (FRAP) were measured at different fermentation times. The results showed that the molecular weight of barley β-glucan was decreased from 1.052 × 10⁵ Da to 4.965 × 10⁴ Da within 0–24 h by L. plantarum dy-1 fermentation, but there was no effect on its characteristic structure. The water- and oil-holding properties of barley β-glucan were significantly enhanced with increased fermentation time, and the fluid viscous behavior of barley β-glucan was enhanced at 6% concentration, while elastic characteristics were weakened. The fermentation had no significant effect on the scavenging effect of DPPH and ABTS radicals of barley β-glucan, but the hydroxyl radical scavenging activity and total antioxidant capacity of FRAP were enhanced with increased fermentation time. Fermentation time may change the physicochemical properties and enhance antioxidant activity of barley β-glucan by reducing its molecular weight.

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Increase the study on the effect of lactic acid bacteria fermentation on the antioxidant activity of barley β-glucan.

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The water-retaining and oil-controlling properties of barley β-glucan increased significantly.

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Fermentation time may enhance physicochemical properties and antioxidant activity of barley β-glucan.

Characterization of acid hydrolysates from barley β-glucan concentrate for their physico-chemical and rheological properties

The present study was aimed at assessing the influence of acid hydrolysis on the physicochemical and rheological properties of β-glucan concentrate. Barley β-glucan concentrate was subjected to acid hydrolysis for 30 and 60 min. The molecular weight and viscosity were observed to be a function of hydrolysis time and decreased in a duration-based approach. Significant reduction in water binding capacity and swelling power was observed after acid hydrolysis. Acid hydrolysis dramatically altered the flow properties and a Newtonian behavior was observed for HBG₆₀. The oscillatory measurements revealed enhanced visco-elasticity for HBG₃₀ solutions in comparison to its native counterpart and were greatly reliant on molecular weight and concentration. DSC measurements showed reduced thermal stability of acid hydrolysates in comparison to native β-glucan concentrate. Overall, this study provides useful information on the hydration, thermal and rheological behavior of β-glucan concentrates and could be helpful in optimizing the concentration of β-glucan concentrates in food formulations.

Rheological and Microstructural Properties of Xanthan Gum-Based Coating Solutions Enriched with Phenolic Mango (Mangifera indica) Peel Extracts

Mango (Mangifera indica) is a tropical fruit highly desired for its vitamin content and flavor, but its peel is considered a byproduct or waste. However, mango peel contains some bioactive compounds that improve food quality matrix for the development of edible coatings or films. The effect of phenolic mango (Mangifera indica) peel extracts on the physicochemical, rheological, and microstructural properties of xanthan gum-based coating solutions was evaluated. The obtained solutions were stable during the study period and presented a non-Newtonian fluid type shear-thinning behavior described by Ostwald-de Waele. Moreover, viscoelastic properties revealed that the elastic modulus was higher than the viscous modulus, showing a characteristic of weak gels. The addition of extracts did not alter the shear rate and viscoelastic character of the solutions, preserving the pseudoplasticity and weak gel behavior of xanthan gum associated with spreadability and adherence of coatings; it modified the gel structure as a function of temperature. Furthermore, the coating solutions of xanthan gum and phenolic mango peel extracts are an alternative to develop complex food systems such as edible coatings, edible films, or delivery systems.

Pectin from Citrus Canning Wastewater as Potential Fat Replacer in Ice Cream

Pectin had been recovered from canning wastewater produced by chemical treatment of segment membrane during preparation of canned citrus in our previous research. The purpose of this study was to characterize the extracted pectin from canning wastewater, and to evaluate its application as a fat alternative to replace fat in ice cream. The monosaccharide composition and rheological properties of the pectin were determined. The influences of fat reduction and pectin addition on the physicochemical, rheological and sensory properties of low-fat ice cream were determined. The rheological results showed that pectin solutions were typical pseudoplastic fluids. The addition of pectin in ice cream can cause an increase in viscosity, overrun, and hardness, and a decrease in meltdown of the ice cream. When 0.72% pectin (w/w) is incorporated into ice cream, a prototype product of ice cream with 45% lower fat content compared to the control was made. Results indicated that their qualities such as appearance, flavor, and taste were not significantly different. The low-fat ice cream had higher smoothness scores and lower mouth-coating scores. Hence, pectin extracted from citrus canning wastewater can be potentially used as fat replacer in ice cream, which benefits both the environment and the food industry.

Studies on the Physicochemical and Processing Properties of Tremella fuciformis Powder

Tremella fuciformis is edible and medicinal food since ancient times in China. In this article, the physicochemical and processing properties of Tremella fuciformis powder (TFS) and synergistic interaction with Lotus seed powder (LTS) in aqueous solution were investigated. The elemental compositions of TFS were 1.71 % N, 47.21 % O, 40.35 % C, 6.25 % H and 0.20 % S. Aspartic and Glutamic acids were the major amino acids in TFS for taken about 0.91 % and 1.12 %. TFS dispersion couldn’t form a gel structure at all selected concentrations until the ratio of TFS: LTS was 1:1 at a total concentration of 36 mg/mL. The network strength of TFS/LTS dispersions increased with the total powder concentrations increased during continuous heating from 25°C to 70°C. Gluten, amorphous and crystalline regions, and amorphous starch were observed in mixtures TFS/LTS compared with TFS. TFS/LTS had a more concavo-convex microstructure than TFS due to starch gelatinization in LTS.

Biological activities of derivatized D-glucans: a review

D-Glucans have triggered increasing interest in commercial applications in the chemical and pharmaceutical sectors because of their technological properties and biological activities. The glucans are foremost among the polysaccharide groups produced by microorganisms with demonstrated activity in stimulating the immune system, and have potential in treating human disease conditions. Chemical alterations in the structure of D-glucans through derivatization (sulfonylation, carboxymethylation, phosphorylation, acetylation) contributes to their increased solubility that, in turn, can alter their biological activities such as antioxidation and anticoagulation. This review surveys and cites the latest advances on the biological and technological potential of D-glucans following chemical modifications through sulfonylation, carboxymethylation, phosphorylation or acetylation, and discusses the findings of their activities. Several studies suggest that chemically modified d-glucans have potentiated biological activity as anticoagulants, antitumors, antioxidants, and antivirals. This review shows that in-depth future studies on chemically modified glucans with amplified biological effects will be relevant in the biotechnological field because of their potential to prevent and treat numerous human disease conditions and their clinical complications.