title: Change of biological activities of (1----3)-beta-D-glucan from Grifola frondosa upon molecular weight reduction by heat treatment.
abstract: Changes of biological activities manifested by (1----6)-branched (1----3)-beta-D-glucans of various molecular weights obtained by heat treatment of the corresponding intact beta-glucan at 150 degrees C (HD-LE) were examined. The activities assessed in this study were as follows: an antitumor activity, activation of alternative complement pathway, glucose consumption by macrophages, macrophage-mediated lysosomal enzyme activity in culture supernatant and cell lysate, interleukin-1 (IL-1) activity, and adjuvant activity. HD-LE could be classified into three groups: 1) HD-LE 0 h (MW 800000) which activated all of the biological activities tested, 2) HD-LE 0.5 and 3 h (MW 250000 and 21000) which lacked or exhibited low levels of activities such as activation of alternative complement pathway and lysosomal enzyme secretion, 3) HD-LE 6 h (MW 6400) which only activated glucose consumption and synthesis of lysosomal enzyme. These results suggest that an antitumor glucan is not always a multiple enhancer of host defense mechanisms and that a large molecular weight is required to augment multiple immunological activities.
authors.affiliation: Laboratory of Immunopharmacology of Microbial Products, Tokyo College of Pharmacy, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Adachi
authors.forename: N
authors.initials: N
authors.lastname: Ohno
authors.forename: M
authors.initials: M
authors.lastname: Ohsawa
authors.forename: S
authors.initials: S
authors.lastname: Oikawa
authors.forename: T
authors.initials: T
authors.lastname: Yadomae
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents; D001487:Basidiomycota / Q000378:metabolism*; D005936:Glucans / Q000032:analysis* / Q000494:pharmacology; D006358:Hot Temperature; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008970:Molecular Weight; D011124:Polyporaceae / Q000378:metabolism*; D047071:beta-Glucans
chemical_list: D000970:Antineoplastic Agents; D005936:Glucans; D047071:beta-Glucans; C033363:beta-1,3-glucan