Sucrose is a disaccharide composed of glucose and fructose. If a sample of hydrolyzed sucrose containing both glucose and fructose were treated with acidified potassium permanaganate (KMnO4), both sugars would react and be oxidized. KMnO4 is a very strong oxidizing agent and will react with almost any regular sugar molecule. Sugars (monosaccharides) are composed of carbon, hydrogen, and oxygen and contain many hydroxyl groups (OH). KMnO4 readily oxidizes carbons with hydroxyl groups attached to them to ultimately produce CO2 and water (H2O). So both glucose and fructose will reduce the permanganate and will probably do so at fairly equal rates.