Characterisation of the extracellular polysaccharides produced by isolates of the fungus Acremonium

Solid state 13C NMR studies of the extracellular glucans from the fungi Acremonium persicinum C38 (QM107a) and Acremonium sp. strain C106 indicated a backbone of (1→3)-β-linked glucosyl residues with single (1→6)-β-linked glucosyl side branches for both glucans. Analyses of enzymatic digestion products suggested that the average branching frequency for the A. persicinum glucan (66.7% branched) was much higher than that of the Acremonium sp. strain C106 glucan (28.6% branched). The solid state 13C NMR spectra also indicated that both glucans are amorphous polymers with no crystalline regions, and the individual chains are probably arranged as triple helices.