Characterization of a neutral polysaccharide from pumpkin (Cucurbita moschata Duch) with potential immunomodulatory activity

Int J Biol Macromol. 2021 Aug 10:S0141-8130(21)01712-8. doi: 10.1016/j.ijbiomac.2021.08.053. Online ahead of print.ABSTRACTA neutral polysaccharide designated as CMDP-1a (molecular mass 9.263 kDa) was isolated from Cucurbita moschata Duch through hot water extraction, ethanol precipitation, and column chromatography. On the basis of methylation, fourier-transform infrared, monosaccharide composition, and one- and two-dimensional nuclear magnetic resonance spectroscopy analyses, the structure of CMDP-1a was determined to be a backbone composed of α-1,4 linked glucopyranosyl residues with α-Glcp residue linkage at backbone C-6. Atomic force microscopy and scanning electron microscopy analyses revealed that CMDP-1a had a spherical conformation in solution. In immunostimulation assays, CMDP-1a promoted the proliferation of RAW 264.7 macrophages and significantly enhanced their pinocytic and phagocytic capacity. Furthermore, CMDP-1a induced the M1 polarization of original macrophages and the conversion of macrophages from M2 to M1, thereby modulating the balance of M1/M2 macrophages. These results indicated that CMDP-1a might be a potential immunomodulator for food purposes.PMID:34389393 | DOI:10.1016/j.ijbiomac.2021.08.053
Source: International Journal of Biological Macromolecules - Category: Biochemistry Authors: Source Type: research