Abstract
Methods for differential determination of 3-ketosucrose and 3-ketoglucose were established. For determination of 3-ketosucrose, alkaline treatment with 0.1N NaOH was found to be most effective. In this method, 3-ketosucrose gave a characteristic absorption spectrum with a molar extinction coefficient of 6.5×103M-1cm-1 at 340mμ, while 3-ketoglucose did not show a significant absorption spectrum within a range from 300 to 400mμ.
By mixing with 0.2M phosphate buffer, pH 7.0, 3-ketoglucose gave a characteristic absorption spectrum with a molar extinction coefficient of 3.8×103M-1cm-1 at 310mμ, while 3-ketosucrose showed little absorbance.
From the reduction rate of 2, 6-dichloroindophenol with 3-ketoglucose, the ketosugar was determined. 3-Ketosucrose was not able to reduce the reagent at all.
The methods established here were not affected by fructose.
