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

A polysaccharide-enriched extract obtained from Lentinula edodes was submitted to several purification steps to separate three different D-glucans with β-(1→6), β-(1→3),(1→6) and α-(1→3) linkages, being characterized through GC–MS, FT-IR, NMR, SEC and colorimetric/fluorimetric determinations. Moreover, in vitro hypocholesterolemic, antitumoral, anti-inflammatory and antioxidant activities were also tested. Isolated glucans exerted HMGCR inhibitory activity, but only β-(1→6) and β-(1→3),(1→6) fractions showed DPPH scavenging capacity. Glucans were also able to lower IL-1β and IL-6 secretion by LPS-activated THP-1/M cells and showed cytotoxic effect on a breast cancer cell line that was not observed on normal breast cells. These in vitro results pointed important directions for further in vivo studies, showing different effects of each chemical structure of the isolated glucans from shiitake mushrooms.
This research was supported by national R + D program from the Spanish Ministry of Science and Innovation (Project AGL2014-56211-R) and the regional program from the Community of Madrid, Spain (S2013/ABI-2728). Part of this study was also financed by the Brazilian funding agencies Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) – Finance Code 001 and the Fundação Araucária.