Isolation and comparison of α- and β-D-glucans from shiitake mushrooms (Lentinula edodes) with different biological activities

•Three purified glucan fractions were obtained from shiitake mushrooms.•A branched (1→3),(1→6)-β-D-glucan and a linear (1→3)-α-D-glucan were isolated.•A linear (1→6)-β-D-glucan-enriched fraction was also obtained.•Glucans showed in vitro hypocholesterolemic and immunomodulatory activities.•The main differences were observed on in vitro antioxidant and antitumoral activity.