Higher Saccharides Research Articles

Isolation of isomaltose [6-(α- d-glucopyranosyl) d-glucose] from the culture filtrate of Penicillium chrysogenum Q-176

A method for the isolation of isomaltose [6-(α- d-glucopyranosyl) d-glucose] from the culture filtrates of Penicillium chrysogenum Q-176 using maltose as the carbohydrate substrate is described. The method is based on the complete conversion of maltose into isomaltose and other higher saccharides by the mold, followed by fractionation of the products formed in the culture filtrates on a column of charcoal (Norit A), water and 5% ethanol being used as solvents for elution of glucose and isomaltose. Characterization of the sugar by its derivatives is given. The carbohydrate composition of the fractions was determined by circular paper chromatographie technique.

CARBOHYDRATE COMPOSITION OF WORT AND BEER

Carbohydrates up to the nonasaccharide level in wort and beer have been separated by descending paper chromatography, and determined by a colorimetric procedure. In wort there have been found: fructose, glucose, sucrose, maltose, trisaccharide, tetrasaccharide, pentasaccharide, hexasaccharide, heptasaccharide, octasaccharide and nonasaccharide; in beer there have been found: maltose, iso-maltose (6-α-glucosidoglucose) and at least two trisaccharides which have not been studied separately. In the beer chromatogram one very faint spot has been detected just below maltose and another above isomaltose; these have not been identified. Otherwise, the same higher saccharides are present as in wort. Pentoses have not been detected in wort or beer. Individual carbohydrates have been identified by appropriate chemical and physical methods, and the amount of fermentable sugars in wort has been compared with limit attenuation results, good agreement being found. A new solvent, viz. ethyl acetate-acetic acid-water-ethyl alcohol in the ratios 9: 3: 9: 1, has been introduced for the chromatographic separation of carbohydrates higher than trisaccharide.