Abstract
An extract from germinated peas was analyzed for sugars by the methods of Somogyi, Hagedorn‐Jensen and by paper partition chromatography. While the last named method can be controlled and has been shown to give good and reliable results, both the reduction of copper in alcaline solution and the reduction of ferricyanide gave too high values for reducing sugar. The difference was especially great with ferricyanide as oxidising agent (more than 300% reducing sugar compared to the sum of the values for glucose and fructose obtained by paper chromatography). Determination of non‐reducing sugar (only saccharose) by hydrolysis of the extract and measurement of its increase in reducing power by one of the first named methods was too unreliable as other substances were also hydrolyzed with liberation of reducing components. As the amount of surplus reduction by foreign substances cannot be foreseen and is different for different extracts the only reliable method for sugar analysis in biological fluids of varying composition is the separation of the soluble carbohydrates from the interfering substances by partition chromatography and determination of the isolated sugars by one of the classical methods.