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|Section2= |Section3= }} Steviol is a diterpene first isolated from the plant ''Stevia rebaudiana'' in 1931.〔 Its chemical structure was not fully elucidated until 1960.〔 Steviol occurs in the plant as steviol glycosides, sweet compounds that have found widespread use as sugar substitutes.〔 ==Biosynthesis== In ''Stevia rebaudiana'', the biosynthesis of steviol is confined to green tissues. The precursors of steviol are synthesized via the non-mevalonate pathway located in plant cell plastids, which produces isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP). IPP and DMAPP are converted to geranylgeranyl diphosphate (GGDP), which is the precursor of many diterpenoids, by GGDP synthase. GPDP is made into a cyclic compound, copalyl diphosphate (CDP), by CDP synthase, after which kaurene is produced by another cyclization catalyzed by kaurene synthase. The kaurene is then transferred to the endoplasmic reticulum, where it is oxidized to kaurenoic acid by kaurene oxidase in a reaction that uses up oxygen and NADPH. Then steviol is produced by hydroxylation. The steviol is subsequently glycosylated in the cytoplasm.〔 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「steviol」の詳細全文を読む スポンサード リンク
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