The Hemicelluloses. Part IV

Abstract

Two hemicelluloses were isolated, one precipitated by acid, hemicellulose A, the other precipitated from the acid filtrate by alcohol, hemicellulose B. A yields upon hydrolysis xylose and CO2 in amounts corresponding to 11% glycuronic acid. B yields upon hydrolysis arabinose, a little galactose, and CO2 in amounts corresponding to 63% galacturonic acid. The acids decompose during hydrolysis. Hemicelluloses are not, as originally thought, true carbohydrates, but contain acid radicals.