[#1985-07] Structural Characterization of a Neutral Antitumor Beta-D-Glucan Extracted with Hot Sodium Hydroxide from Cultured Fruit Bodies of Grifola frondosa, K. Iino et al.

Structural Characterization of a Neutral Antitumor Beta-D-Glucan Extracted with Hot Sodium Hydroxide from Cultured Fruit Bodies of Grifola frondosa

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

a) Laboratory of Immunopharmacology of Microbial Proudcts, Tokyo College of Pharmacy, b) Nippon Beet Sugar Mfg. Co. Ltd.

The structural characterization of an antitumor beta-D-glucan (grifolan-7N) obtained from the hot sodium hydroxide extract of Grifola frondosa ( maitake ), is described. Grifolan-7N, purified by digestion with alpha-amylase, precipitation with ethanol, and chromatography on Con-A-Sepharose, gave a single and symmetrical peak on gel filtration with Sepharose CL-4B (0.2M NaOH/8M Urea) and had a molecular weight of ~ 1,200,000. The results of methylation analysis, C13-NMR spectroscopy, Smith degradation, and enzymic digestion indicated grifolan-7N to be a (1-3) -linked beta-D-glucan having a single beta-D-glucopyranosyl group attached to position 6 of almost every third backbone unit. Grifolan-7N showed potent activity against the solid Sarcoma 180 in mice.