Dextran is an α-D-1,6-glucose-linked glucan with side-chains 1-3 linked to the backbone units of the Dextran biopolymer. The degree of branching is approximately 5%. The branches are mostly 1-2 glucose units long. Dextran can be obtained from fermentation of sucrose-containing media by Leuconostoc mesenteroides B512F.
A fragment of the Dextran structure is illustrated in Figure 1.