Hemicelluloses of Wheat
نویسنده
چکیده
In 1890, 2 years before the term ^^hemicellulose" was introduced into chemical Uterature by Schulze (12) j^ Allen and ToUens (1) extracted wheat straw with alkali and obtained a product that on hydrolysis afforded ¿-xylose. In 1901 Salkowski (11) extracted wheat straw with boiling 6-percent sodium hydroxide solution and showed that the xylan could be precipitated from the alkaline extract by means of Fehling's solution and thus freed of certain impurities. Heuser, Braden, and Kürschner (6) improved Salkowski's method, and in order not to contaminate their product with lignin, they used bleached straw pulp (method of delignification not given) as their starting material. They obtained a product that was 96 percent xylan. The investigation reported in this paper was undertaken for the purpose of determining the character and composition of the hemicelluloses of wheat straw by methods recently developed.
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