Isolation and structural identification of the homogeneous polysaccharide CGPA1 from Calvatia gigantea with wound healing effects

Calvatia gigantea is a traditional Chinese medicinal fungus known for its diverse pharmacological effects, with polysaccharides being one of its main bioactive components. In this study, a novel homogeneous water-soluble polysaccharide (CGPA1) was successfully isolated and purified from the fruiting body of Calvatia gigantea . The molecular weight of CGPA1 was determined to be 11.69 kDa. Structural characterization was performed using a combination of high-performance gel permeation chromatography (HPGPC), Fourier-transform infrared spectroscopy (FTIR), methylation analysis, and nuclear magnetic resonance (NMR) spectroscopy. The analysis data revealed that CGPA1 is primarily composed of galactose, methyl-galactose, mannose, xylose, and glucose in a molar ratio of 60.01:27.16:10.34:1.83:0.67. The backbone structure predominantly consists of α-1,6-Gal-(1 → and α-1,6 (3-MeO)-Gal-(1→, with side chains of α-Gal and α-Man. Morphological analysis using SEM, XRD, and AFM, combined with Congo red experiments, suggesting that CGPA1 adopts an amorphous granular chain conformation. Both in vitro and in vivo tests confirmed that CGPA1 can promote the migration of MSF cells and accelerate the healing of acute injured wounds. It was found to facilitate skin re-epithelialization, and collagen deposition over the healing process.