title: Growth-inhibitory activity of the D-mannan of Saccharomyces cerevisiae X2180-1A-5 mutant strain against mouse-implanted sarcoma 180 and Ehrlich-carcinoma solid tumor.
abstract: The D-mannan of Saccharomyces cerevisiae X2180-1A-5 mutant strain, which possesses a main chain composed of alpha-(1 yields 6) linked D-mannopyranosyl residues and a small proportion of branches composed of alpha-(1 yields 2)- and alpha-(1 yields 3)-linked D-mannopyranosyl residues, showed strong growth-inhibitory activity against mouse-implanted Sarcoma 180 and Ehrlich-carcinoma solid tumor. The observation that the level of this activity was nearly identical with that of the D-mannan of a wild-type strain of bakers' yeast, which possesses a high proportion of branches composed of alpha-(1 yields 2)-and alpha-(1 yields 3)-linked D-mannopyranosyl residues, suggests that the branches are not essential for antitumor activity. The partial acid-degradation products of both D-mannans, the molecular weight of which was one-third of that of each parent D-mannan, had only one half of the antitumor activity of the parent D-mannans. This suggests that molecular size is the most important factor for the differences in acitvity of the polysaccharides of wild and mutant strains.
mesh_terms: D000818:Animals; D002286:Carcinoma, Ehrlich Tumor / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D008351:Mannans / Q000627:therapeutic use*; D051379:Mice; D011134:Polysaccharides / Q000627:therapeutic use*; D012441:Saccharomyces cerevisiae / Q000032:analysis*; D012510:Sarcoma 180 / Q000188:drug therapy*
chemical_list: D008351:Mannans; D011134:Polysaccharides