NURSING ANM AND GNM

Detailed explanation-1: -Fructose and sucrose are two common sugars which give a positive test. Sucrose gives a positive test as it is a disaccharide consisting of fructose and glucose. Generally, 6M HCl is used to run this test. Ketoses are dehydrated faster and give stronger colors.

Detailed explanation-2: -Iodine Test: Principle, reagents, Procedure and Result On heating or on addition of alkali; the coiled structure becomes linear and the I2 molecules are released and the color disappears. The test will be answered by fructose, sucrose and other keto containing carbohydrates.

Detailed explanation-3: -Chemical test Sucrose (table sugar) contains two sugars (fructose and glucose) joined with by their glycosidic bond in such a way as to prevent the glucose isomerizing to aldehyde, or the fructose to alpha-hydroxy-ketone form. Sucrose is thus a non-reducing sugar which does not react with Benedict’s reagent.

Detailed explanation-4: -The test is commonly used for reducing sugars but is known to be NOT specific for aldehydes. For example, fructose gives a positive test with Fehling’s solution as does acetoin.