Structural characterization of polysaccharides from Polygonatum Sibiricum and effect on alleviating hyperlipidemia in...

Polysaccharides are the major bioactive composition of Polygonatum sibiricum (P. sibiricum). However, the structural and functional identifications of these polysaccharides were still limited. Herein, we isolated a novel P. sibiricum polysaccharides (PSPF) and explored its potential function and mechanism in alleviating hyperlipidemia. PSPF were purified by diethylaminoethyl-sepharose fast flow (DEAE-Sepharose FF) and cross-linked dextran gel LH-20 (Sephadex LH-20) column chromatography, and identified by gel-permeation chromatography, methylation analysis, fourier transform infrared spectrometer (FT-IR), nuclear magnetic resonance (NMR), and gas chromatography-mass spectrometry (GC-MS). Their molecular weight (Mw), polysaccharide composition, and chemical structure were characterized. Furthermore, egg yolk emulsion-induced acute hyperlipidemia mouse model was constructed to evaluate the lipid-lowering efficacy and the underlying mechanism of PSPF. It was found that PSPF, with the Mw of 3592 Da, were prepared and mainly consisted of fructan with →1)-β-D-Fruf-(2 → main chain and →6)-β-D-Fruf-(2 → side chains. In addition, PSPF supplements efficiently reduced liver lipid accumulation, alleviated hepatocyte steatosis, and upregulated the AMP-activated protein kinase (AMPK) pathway, thereby enhancing fatty acid oxidation and decomposition. These results indicate that PSPF may serve as the potential dietary supplements for lipid reduction.