Cereal Chem 55:952 - 966.  |  VIEW ARTICLE
Interaction of Some Dyes with Cereal Beta-Glucans.

P. J. Wood and R. G. Fulcher. Copyright 1978 by the American Association of Cereal Chemists, Inc. 

Low concentration of the dyes Calcofluor White M2R New, Tinopal CBS-X, and Congo Red cause preferential precipitation of beta-glucan from aqueous solutions of oat gum containing protein, pentosan, and starch. Tests with a number of polysaccharides indicate a specificity for beta-1,4-linked glucopyranosyl units. The precipitation with Calcofluor occurs between pH6 and 10 and is not appreciably affected by temperature (5 and 25 C), but the precipitate dissolves at elevated temperatures. Salt suppresses the precipitation. Viscosity measurements and absorption spectrophotometry afford other evidence for specific dye-polysaccharide complex formation. The dyes concerned are useful in microscopic studies of oat and barley endosperm cell walls, and can be used to observe the changes that occur during extraction of oat gum.