Chemical properties and antioxidant activity of exopolysaccharides fractions from mycelial culture of Inonotus obliquus in a ground corn stover medium

► Exopolysaccharide fractions of Inonotus obliquus in submerged fermentation. ► The fractions from the control medium and the corn stover-containing medium. ► The fractions from the corn stover medium had stronger antioxidant activities. ► Lignocellulose decomposition significantly enhanced the antioxidant activity. ► Lignocellulose decomposition changed the chemical characterisation of fractions.