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|Section2= |Section6= |Section7= }} Fructose, or fruit sugar, is a simple ketonic monosaccharide found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. It is one of the three dietary monosaccharides, along with glucose and galactose, that are absorbed directly into the bloodstream during digestion. Fructose was discovered by French chemist Augustin-Pierre Dubrunfaut in 1847.〔Dubrunfaut (1847) ("Sur une propriété analytique des fermentations alcoolique et lactique, et sur leur application à l'étude des sucres" ) (On an analytic property of alcoholic and lactic fermentations, and on their application to the study of sugars), ''Annales de Chimie et de Physique'', 21 : 169–178. On page 174, Dubrunfaut relates the discovery and properties of fructose.〕〔Fruton, J.S. Molecules of Life 1972, Wiley-Interscience〕 The name "fructose" was coined in 1857 by the English chemist William Miller.〔William Allen Miller, ''Elements of Chemistry: Theoretical and Practical'', Part III. Organic Chemistry (London, England: John W. Parker and son, 1857), (pages 52 and 57 ).〕 Pure, dry fructose is a very sweet, white, odorless, crystalline solid and is the most water-soluble of all the sugars. Fructose is found in honey, tree and vine fruits, flowers, berries, and most root vegetables. Commercially, fructose is frequently derived from sugar cane, sugar beets, and corn. Crystalline fructose is the monosaccharide, dried, ground, and of high purity. High-fructose corn syrup (HFCS) is a mixture of glucose and fructose as monosaccharides. Sucrose is a compound with one molecule of glucose covalently linked to one molecule of fructose. All forms of fructose, including fruits and juices, are commonly added to foods and drinks for palatability and taste enhancement, and for browning of some foods, such as baked goods. About 240,000 tonnes of crystalline fructose are produced annually.〔Wolfgang Wach "Fructose" in Ullmann's Encyclopedia of Industrial Chemistry 2004, Wiley-VCH, Weinheim.〕 Excess fructose consumption has been hypothesized to be a cause of insulin resistance, obesity,〔 elevated LDL cholesterol and triglycerides, leading to metabolic syndrome.〔〔 Fructose encourages visceral adipose tissue build-up and ectopic fat deposition.〔 The majority of studies indicate there may be an increased risk of cardiovascular disease from a high intake of fructose.〔 == Chemical properties == Fructose is a 6-carbon polyhydroxyketone. Crystalline fructose adopts a cyclic six-membered structure owing to the stability of its hemiketal and internal hydrogen-bonding. This form is formally called D-fructopyranose. In solution, fructose exists as an equilibrium mixture of 70% fructopyranose and about 22% fructofuranose, as well as small amounts of three other forms, including the acyclic structure. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Fructose」の詳細全文を読む スポンサード リンク
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