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Cereal Chem 45:99 - 108.  |  VIEW ARTICLE
The Oxidation-Reduction Enzymes of Wheat. IV. Qualitative and Quantitative Investigations of the Oxidases.

G. R. Honold and M. A. Stahmann. Copyright 1968 by the American Association of Cereal Chemists, Inc. 

Qualitative and quantitive studies of oxidases in whole wheat and five milling fractions of two hard red winter (Triumph and Bison) and spring (Lee and Selkirk) wheats were conducted. Qualitative data were obtained by polyacryamide-gel electrophoresis, and quantitative information by spectrophotometric and manometric techniques. The enzymes studied were peroxidase, cytochrome oxidase, catalase, ascorbate oxidase, indoleacetic acid oxidase, and polyphenol oxidase. Qualitatively, gel-electrophoretic patterns were similar in all varieties for peroxidase and catalase. Two catalase isoenzymes and eight peroxidase isoenzymes were detected, two of which migrated toward the cathode at pH 8.9. The activity of both enzymes was much higher in spring wheat than winter wheat. Catalase activity was four to 8 times higher in bran than flour and peroxidase was five to thirteen times higher in bran. It appeared that the cytochrome oxidase bands observed on gels were due to peroxidase. Only trace amounts of ascorbate oxidase and polyphenol oxidase were detected in spring and winter wheats. Polyphenol oxidase activity was too low to be detected on gels. Indoleacetic acid oxidase activity was detected in winter wheat only.

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