Ultrasound-Assisted Extraction, Antioxidant and Anticancer Activities of the Polysaccharides from Rhynchosia minima Root

Box-Behnken design (BBD), one of the most common response surface methodology (RSM) methods, was used to optimize the experimental conditions for ultrasound-assisted extraction of polysaccharides fromRhynchosia minimaroot (PRM). The antioxidant abilities and anticancer activity of purified polysaccharide fractions were also measured. The results showed that optimal extraction parameters were as follows: ultrasound exposure time, 21 min; ratio of water to material, 46 mL/g; ultrasound extraction temperature, 63 °C. Under these conditions, the maximum yield of PRM was 16.95% ± 0.07%. Furthermore, the main monosaccharides of purified fractions were Ara and Gal. PRM3 and PRM5 exhibited remarkable DPPH radical scavenging activities and reducing powerin vitro. PRM3 showed strong inhibitory activities on the growth of MCF-7 cellsin vitro. The above results indicate that polysaccharides fromR. minimaroot have the potential to be developed as natural antioxidants and anticancer ingredients for the food and pharmaceutical industries.Keywords:Rhynchosia minimaroot;polysaccharide;ultrasound-assisted extraction;antioxidant activity;anticancer activity