Fructose

fructose (frŭk`tōs), levulose (lĕv`yəlōs'), or fruit sugar, simple sugar found in honey and in the fruit and other parts of plants. It is much sweeter than sucrose (cane sugar). It is best obtained by hydrolysis of inulin, a polysaccharide found in dahlia bulbs and the Jerusalem artichoke. Chemically it is a monosaccharide (see carbohydrate) with the empirical formula C₆H₁₂O₆. It has the same formula as glucose but differs from it in structure (see isomer). It is often found with glucose in nature. Glucose and fructose are formed in equal amounts when sucrose is hydrolyzed by the enzyme invertase or by heating with dilute acid; the resulting equimolar mixture of fructose and glucose, called invert sugar, is the major component of honey. Fructose reacts with Fehling's solution and can be differentiated from glucose by its reaction with lime water to form a water-insoluble precipitate, calcium fructosate. In solution, fructose exists as a ring compound in equilibrium with a straight-chain form.

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fructose

 or levulose or fruit sugar

Organic compound, one of the simple sugars (monosaccharides), chemical formula C₆H₁₂O₆. It occurs in fruits, honey, syrups (especially corn syrup), and certain vegetables, usually along with its isomer glucose. Fructose and glucose are the components of the disaccharide sucrose (table sugar); hydrolysis of sucrose yields invert sugar, a 50:50 mixture of fructose and glucose. The sweetest of the common sugars, fructose is used in foods and medicines.

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Fructose

A sugar that is the commonest of ketoses and the sweetest of the sugars. It is also known as d -fructose, d -fructopyranose, and levulose fruit sugar. It is found in free state, usually accompanied by d -glucose and sucrose in fruit juices, honey, and nectar of plant glands. d -Fructose is the principal sugar in seminal fluid. See Carbohydrate

Fructose is readily utilized by diabetic animals. In persons with diabetes mellitus or parenchymal hepatic disease, the impairment of fructose tolerance is relatively small and not at all comparable to the diminution in their tolerance to glucose. See Monosaccharide