[#1985-01] Structure-Function Relationship of Antitumor β-1,3-Glucan Obtained from Matted Mycelium of Cultured Grifola frondosa, K. Iino et al.

Structure-Function Relationship of Antitumor β-1,3-Glucan Obtained from Matted Mycelium of Cultured Grifola frondosa

Iino, K(a), Ohno, N(a), Suzuki, I(a), Sata, K(b), Oikawa, S(b), Yadomae, T(a)

a) Tokyo College of Pharmacy, b) Nippon Beet Sugar Mfg. Co. Ltd

The structure-function relationship of the antitumor 6-branched β-1,3-glucan (grifolan NMF-5N) extracted from the matted mycelium of Grifola frondosa ( maitake ) was examined by using various chemical modification procedures (periodate oxidation, Smith degradation, and enzymic hydrolysis). The antitumor activity of grifolan NMF-5N was not lowered by periodate oxidation. Partial removal of branches by mild hydrolysis did not affect the activity. However, the linear β-1,3-glucan obtained by Smith degradation lacked antitumor activity. From the results of enzymic hydrolysis of grifolan NMF-5N, this glucan contains aβ-1,3-glucanase-resistant core structure. The core structure is present randomly in this glucan and does not itself show antitumor activity. These results that some of the branches at C-6 in grifolan NMF-5N are important for the antitumor activity, and that the activity requires a relatively high molecular weight.