Preliminary Structure Analysis and Structure Morphology Observation of Alkali-Extractable Polysaccharide PEAP-1 from Pleurotus Eryngii

Abstract:

In this manuscript,the water-soluble crude polysaccharides PEAP was extracted from Pleurotus Eryngii(PE) by alkali solution and fractionated by DEAE-52 cellulose and Sephadex G-150,obtaining a novel polysaccharide composition termed PEAP-1. Furthermore,the structural characteristics of PEAP-1 was analyzed by HPLC,GC,IR,Congo red test,AFM and SEM methods.The results of HPLC and GC analysis indicated that PEAP-1 was a homogeneous polysaccharide whose average molecular weight is 450 kDa and monoaccharide is composed of Glu and Gal at a molar ratio of 16.9∶0.37. Moreover,the peak near 832 cm-1and 919 cm-1suggested the presence of pyranose ring in PEAP-1 from the infrared spectroscopy. The Congo red test and atomic force microscope(AFM) images showed that PEAP-1 has no triple-helix structure but with multi-branched frame,and its single molecular presents random coil chain with a diameter of 0.13~1.2 nm.Meanwhile,the flake,rods and mesh morphology of PEAP-1 was detected using SEM.