Low molecular weight maitake MD-Fraction (Klasma-MD) hydrolyzed with endo-β-1,6-glucanase of Trichoderma harzianum induces antitumor activities

We previously reported that MD-Fraction (Klasma-MD), a specific-structured β-glucan extracted from fruit bodies of maitake mushrooms (Grifola frondosa), can activate cellular immune systems and express antitumor effects. The molecular weight of the MDFraction ranged from 1200000 to 2000000. The molecular weight of the products of the MD-Fraction obtained after hydrolysis by endo-β-1,6-glucanase from Tricoderma harzianum was reduced to 250000 in terms of dextran, and these products inhibited MM-46 carcinoma in C3H/HeJ mice by 67.9% after intraperitoneal injection. In addition, interleukin-12 and interferon-γ values were increased 1.4 fold and 2.1 fold, respectively, compared with control values. From these results, low molecular weight MD-Fraction (L-MD-Fraction) maintains an immunological active site.