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|Section2= }} Shikimic acid, more commonly known as its anionic form shikimate, is a cyclohexene, a cyclitol and a cyclohexanecarboxylic acid. It is an important biochemical metabolite in plants and microorganisms. Its name comes from the Japanese flower ''shikimi'' (シキミ, the Japanese star anise, ''Illicium anisatum''), from which it was first isolated in 1885 by Johan Fredrik Eykman.〔The Botanical Relations of Illicium Religiosum, Sieb., Illicium Anisatum, Lour. J. F. Eykman, American Journal of Pharmacy, 1881, volume 53, Number 8 ((article ))〕 The elucidation of its structure was made nearly 50 years later.〔Liquidambar styraciflua: a renewable source of shikimic acid. Liza B. Enrich, Margaret L. Scheuermann, Ashley Mohadjer, Kathryn R. Matthias, Chrystal F. Eller, M. Scott Newman, Michael Fujinaka and Thomas Poon, Tetrahedron Letters, 2008, volume 49, pages 2503–2505, 〕 It appears in the list of Group 3 carcinogens of the International Agency for Research on Cancer. Group 3 means that the agent is not classifiable as to its carcinogenicity to humans. Nevertheless, it is recommended to roast tree fern fronds, a speciality called ''fiddlehead'' (furled fronds of a young tree fern in the order Cyatheales, harvested for use as a vegetable). These fronds are edible, but must be roasted first to remove shikimic acid.〔Carcinogenicity of bracken and shikimic acid. I. A. Evans and M. A. Osman, Nature, 26 July 1974, volume 250, pages 348 - 349, 〕 Shikimic acid is also the glycoside part of some hydrolysable tannins. == Biosynthesis == Phosphoenolpyruvate and erythrose-4-phosphate react to form 3-deoxy-D-arabinoheptulosonate-7-phosphate (DAHP), in a reaction catalyzed by the enzyme DAHP synthase. DAHP is then transformed to 3-dehydroquinate (DHQ), in a reaction catalyzed by DHQ synthase. Although this reaction requires nicotinamide adenine dinucleotide (NAD) as a cofactor, the enzymic mechanism regenerates it, resulting in the net use of no NAD. : DHQ is dehydrated to 3-dehydroshikimic acid by the enzyme 3-dehydroquinate dehydratase, which is reduced to shikimic acid by the enzyme shikimate dehydrogenase, which uses nicotinamide adenine dinucleotide phosphate (NADPH) as a cofactor. : 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「shikimic acid」の詳細全文を読む スポンサード リンク
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