Somogyi method

Colorimetric Methods. Numerous colorimetric methods exist for the quantitative determination of carbohydrates as a group (8). Among the most popular of these is the phenol—sulfuric acid method of Dubois (9), which rehes on the color formed when a carbohydrate reacts with phenol in the presence of hot sulfuric acid. The test is sensitive for virtually all classes of carbohydrates. Colorimetric methods are usually employed when a very small concentration of carbohydrate is present, and are often used in clinical situations. The Somogyi method, of which there are many variations, rehes on the reduction of cupric sulfate to cuprous oxide and is appHcable to reducing sugars. 

Somogyi method, in sugar analysis, 23 475 Sonication, 16 410-411 Sonic limit, heat pipe, 13 230 Sonogashira coupling... 

When p-nitrophenyl a-L-arabinofuranoside is used, the amount of p-nitrophenol released is assayed by measuring the absorption at 400 nm. When phenyl a-L-arabinofuranoside or beet L-arabinan is used, the amount of L-arabinose produced is measured by the Nelson-Somogyi method.3233... 

For enzyme assay, (1— 5)-L-arabinan is the best substrate.4 Reducing groups produced after enzymic action are determined by the Nelson-Somogyi method. One unit of the enzyme is the amount that liberates one //mol of reducing groups from (1— 5)-L-arabinan per minute at 30°. 

Nelson, N. 1944. A photometric adaptation of the Somogyi method for the determination of glucose. J. Biol. Chem. 153 375-380. 

Estimation of Catalytic Activity. The catalytic activities of the copolymers on the hydrolysis of polysaccharides were estimated, with the measurement of increase in reducing sugar in the reaction mixture with reaction time according to Somogyi method (22). The hydrolysis rates of sucrose were determined from the measurement of optical rotatory power... 

Nelson, N. (1944). A Photometric Adaptation of the Somogyi Method for the Determination of Glucose. J Biol Chem 153 375. 

Somogyi method. Those of OHP with K S 0.5. (Fig. 2) for instance, are composed of an average of ten anhydrogalacturonide residues. 

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