Dextran (mol. wt. 80,000) belongs to the family of neutral polysaccharides, which are recognized as contaminants in sugar processing and other food production industries. These are composed of chains of D-glucose units connected by alpha-(1-6) linkages of varying lengths. They are found as bacterial extracellular polysaccharides and reportedly synthesized from sucrose by beneficial lactic acid bacteria, such as Leuconostoc mesenteroides and Lactobacillus brevis. They are incorporated in bakery products to improve the crumb texture, softness, and loaf volume, as stabilizers and additives in confectionery, flavor extract, icing compositions, beverages including soft drinks, milk, etc.
Dextran has been used as a polymer standard in the quantitative determination of intracellular sodium [Na+] using fluorescence lifetime imaging microscopy (FLIM) with CoroNaGreen dye. It has also been used in combination with concanavalin A as concanavalin A-dextran affinity assay employed in osmotic glucose sensor for the characterization of commercial nanoporous membranes.