Method of producing nitrogen-containing polysaccharides
AssigneeKureha Kagaku Kogyo Kabushiki Kaisha
InventorsSaburo Ueno, Chikao Yoshikumi, Fumio Hirose, Yoshio Omura, Toshihiko Wada, Takayoshi Fujii, Eiichi Takahashi
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Abstract
The fungi belonging to the Coriolus genus is first extracted with water or a dilute alkaline solution and then further extracted stepwise by using alkaline solutions with gradually increased concentrations to obtain a nitrogen-containing polysaccharide having an anti-tumor activity in a high yield.
Claims4
A method of providing a nitrogen-containing polysaccharide substantially free from units having a molecular weight below about 5000 which comprises extracting said nitrogen-containing polysaccharide from a fungus of the genus Coriolus of the family Polyporaceae of the class Basidomycetes at a temperature of 50.degree. to 100.degree. C. wherein:
- (a) a first extraction step is conducted with water or a dilute aqueous alkaline solution;
- (b) a second extraction step is conducted in an alkaline medium having a normality higher than said first extraction step and below about 2.0;
- and
- (c) a third extraction step is conducted at a normality higher than said second extraction step and below about 2.0.
Dependencies are inferred from the claim text.