Ultrasound-Assisted Ionic Liquid Extraction of Polysaccharides From Crataegus songarica K. Koch Fruits: Structural...

In this study, we optimal the ultrasound-assisted ionic liquid extraction (UAILE) process of polysaccharides from Crataegus songarica K. Koch fruits. The optimal conditions determined were ultrasonic power of 400 W, temperature of 79°C, extraction time of 78 min, ethylammonium dodecyl sulfate (EADS) concentration of 1.52 mg/mL, and liquid-solid ratio of 51:1 mL/g. Under these conditions, the polysaccharides yield was 34.37%, which was significantly higher than that obtained by the conventional ultrasound-assisted extraction (UAE) and hot water extraction (HWE) methods. After purification, we studied the chemical composition, physicochemical properties, and structural characteristics of polysaccharides (CSP). The results showed that CSP is a heteropolysaccharide containing α-linkage glucopyranose, which is mainly composed of mannose, arabinose, galactose, and glucose, with a molecular weight (Mw) of 27.82 × 10⁴ Da. In addition, CSP demonstrated significant free radical scavenging ability and was able to efficiently reduce the H₂O₂-induced HepG2 cellular malondialdehyde (MDA) content, while enhancing superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities, showing its superior antioxidant activity. On the basis of these properties, CSP is expected to be used as a novel efficacy factor in the food and pharmaceutical industries.