Chemistry, physico-chemistry and applications linked to biological activities of β-glucans

Abstract

β-Glucans is the common name given to a group of chemically heterogeneous polysaccharides. They are long- or short-chain polymers of (1-->3)-β-linked glucose moieties which may be branched, with the branching chains linked to the backbone by a (1-->6)-β linkage. β-(1-->3)-Glucans are widely distributed in bacteria, algae, fungi and plants, where they are involved in cell wall structure and other biological function. β-Glucans have been shown to provide a remarkable range of health benefits, and are especially important against the two most common conventional causes of death in industrialized countries, i.e. cardiovascular diseases (where they promote healthy cholesterol and blood glucose levels) and cancer (where they enhance immune system functions). This Highlight provides a comprehensive and up-to-date commentary on β-glucans, their chemistry, physico-chemistry, functional role in immunological responses, and possible applications as therapeutic tools. In addition, we discuss the mechanism behind their health benefits, which are not yet fully understood.

High-throughput, Highly Sensitive Analyses of Bacterial Morphogenesis Using Ultra Performance Liquid Chromatography

“…A, chromatograms resulting from injection of 0.2 and 4 l of the same E. coli MG1655 sample yield quantitatively similar peak abundances. Muropeptide labels: M ϭ monomer, D ϭ dimer, T ϭ trimer; (2,3,4,5) indicate the number of amino acid stem peptides; modifications: G ϭ glycine replacing L-alanine, L ϭ two additional amino acids from Pronase E cleavage, D ϭ 3,3-diaminopimelic acid (DAP)-DAP cross-bridge, N ϭ terminating anhydro-muropeptide. B, subtraction of a water blank from the chromatogram produces a baseline with essentially zero absorbance, improving the accuracy of peak abundance quantification.…”

“…Plant, fungal, and algal cells as well as most bacteria have a cell wall surrounding the cytoplasmic membrane that defines the shape of the cell (2) and provides mechanical resistance to expansion due to the osmotic pressure from within the cell (3). In bacteria, the cell wall is an important antibiotic target (4), with treatment often disrupting the integrity of the cell wall and eventually leading to cell lysis (5).…”

β-Glucans and Probiotics

“…β-Linkages-containing sugars are non-digestible to humans, who lack the enzymes able to split such type of glycosidic bond (Barsanti et al, 2011). Despite their unsuitability for nutritional purposes, β-glucans own notable physiological effects which attract much attention and, at the same time, create skepticism.…”

“…Moreover, β-glucans occur in some plants, being usually contained in the endosperm cell walls and in the subaleurone layer of several cereals, such as oat, barley, sorghum, triticale, wheat and rice. β-Glucans from such species generally exhibit a linear chemical structure with β(1,3)-and β(1,4)-D-glycopyranosyl residues, with β(1,2)-or (1,6)-glucopyranosyl branches units (Barsanti et al, 2011).…”

Promising Effects of Beta-Glucans on Metabolism and on the Immune Responses: Review Article

“…Dube et al (2014) used chitosan-coated PLGA nanoparticles functionalized with 1,3-beta-glucan from Euglena gracilis for Dectin-1 targeting and reported an increased intracellular delivery of the encapsulated antituberculosis drug, enhanced pro-inflammatory reaction with relevant production of reactive oxygen and nitrogen species (Cordeiro et al, 2015). It is important to notice that beta-glucan adjuvant properties are different between each other, depending on many configurations of molecular structures, size and branches responsible for the differences (Soltanian et al, 2009;Adams et al, 2008;Barsanti et al, 2011;Sletmoen and Stokke, 2008).…”