Preparation, preliminary characterization and immunostimulatory activity of polysaccharide fractions from the peduncles of Hovenia dulcis

► Polysaccharides from peduncles of Hovenia dulcis (HDPS) were prepared and purified. ► The three purified fractions were mainly composed of Rha, Ara, Gal and GalA. ► The three purified fractions had potent immunostimulatory activities in vitro. ► HDPS-1 exhibited relative higher immunostimulatory activity in vitro.