A β-glucan from the fruit bodies of edible mushrooms Pleurotus eryngii and Pleurotus ostreatoroseus

The glucans of basidiomycetes are an important class of polysaccharides with potential biological activities. In this work, the beta-glucans were isolated from the fruiting bodies of edible mushrooms, Pleurotus eryngii and Pleurotus ostreatoroseus, via extraction with hot water, and then fractionation by freeze-thawing. The insoluble glucans gave similar C-13 NMR spectra, monosaccharide composition and methylation analyses, and P. eryngii was selected for further controlled Smith degradation, and DEPT and H-1 (obs.), C-13 HMQC spectroscopy. It was a branched beta-glucan, with a main chain of (1 -> 3)-linked-Glcp residues, substituted at O-6 by single-unit beta-Glcp side-chains, on average to every third residue of the backbone, as in scleroglucan. (c) 2006 Published by Elsevier Ltd.