Structural characterization of a water-soluble polysaccharide from the fruiting bodies of Agaricus bisporus

Abstract

An edible fungal polysaccharide termed as ABP was obtained by extraction with hot water, and followed successive chromatographic purification using DEAE-Sepharose Fast Flow column and Sephacryl S-300 High-Resolution column. A symmetrical peak was obtained on high-performance size-exclusion chromatography with an average molecular weight of 5.17 × 104 Da, which was named ABP, and its main components were D-glucose and D-mannose. Based on the study of methylation analysis, along with FT-IR, GC, GC-MS, 1D 1H and 13C NMR and 2D NMR (H-HCOSY, TOCSY, HMQC, and NOESY), its chemical structure was featured with a repeating unit (1→6) linking β-D-Glcp as the main backbone with (1→4)-linked α-D-Manp units. The structure of the mainly repeating units of ABP was established as: →6) - β - D - Glucp - (1→4) - α - D - Manp(1→6) - β - D - Glucp - (1→6) - β - D - Glucp - (1→. © 2014 by the authors; licensee MDPI, Basel, Switzerland.