Comparative Structural Characterisation and In Vitro Bioactivities of Crude and Purified Polysaccharides from Dandelion (Taraxacum officinale) Root Using Microwave-Assisted Enzymatic Extraction

The increasing demand for functional products has promoted research on bioactive compounds. Dandelion root polysaccharide (DRP), a key bioactive component of Taraxacum officinale, has anti-inflammatory, antioxidant, hypoglycemic and hypolipidemic activities. This study extracted DRP via microwave-assisted enzymatic extraction (MAEE) to obtain mDRP, and isolated acidic polysaccharide mDRP-1 (7.548 kDa) by column chromatography. HPLC showed that both contain six monosaccharides (Man, Rha, GalA, Glu, Gal, Ara) with different molar ratios. mDRP is heterogeneous (trace protein/nucleic acids, no triple helix, amorphous), while mDRP-1 has a triple-helical, semi-crystalline structure; both have characteristic polysaccharide peaks and pyranose rings, and rough, porous surfaces. mDRP had better thermal stability and significant concentration-dependent in vitro antioxidant and hypoglycaemic effects.