Question

Glycogen and starch both give a (+) test with I2-KI and a (-) test with Benedict's. If you hydrolyzed these two polysaccharides and tested the solutions with the same two reagents what resuts would you get? Explain these results.

Answer 1

Potassium iodide reacts with polysaccharides and results blue color, and gives negative results with monosaccahrides. Benditcts reagent reacts with monosaccharides and gives color on the basis of monosaccharide concentration and gives neative results with polysaccharides.

If you hydrolyze the glygocen and starch those forms glucose molecules and gives positive wit bendicts reagent. The color internisty is depends on the available reducing sugar it starts from green to brick red.