An efficient and environmentally-friendly extraction, characterization and activity prediction of polysaccharides from Rhizoma et Radix Notopterygii

Traditional hot water reflux extraction, ultrasonic-water extraction (UW), ultrasonic-natural deep eutectic solvent (NADES) extraction (U-NADES), ultrasonic-water and enzyme extraction (U-W-E) and ultrasonic-NADES and enzyme extraction (U-NADES-E) are employed for the extraction of Rhizoma et Radix Notopterygii polysaccharides (RNP), in which, the U-NADES-E has being proved as the most effective method. Response Surface Methodology (RSM) was utilized to optimize the conditions for U-NADES-E method. Using the optimal extraction conditions, the yield of RNP can be enhanced by nearly two-fold in comparison to the traditional extraction method, achieving a yield of 7.38 %, with a mere 30-min treatment and low ultrasonic power at 240 W. The RNP's composition included Rhamnose, Arabinose, Galactose, Glucose and Galacturonic Acid by high-performance anion-exchange chromatography. The polysaccharides from two different species of Rhizoma et Radix Notopterygii have also been characterized and identified. Network pharmacology and molecular docking predict that RNP may exert its effects in vivo through binding to PPARA, ACE and REN proteins, thereby potentially impacting diabetes outcomes. This study proposes a new, efficient, energy-saving and environmentally-friendly method for the extraction of RNP.