甜菊醇糖苷生物合成及关键酶研究进展

Advances on the Steviol Glycoside Biosynthesis and Its Key Enzymes

甜菊醇糖苷(steviol glycosides,SGs)是甜叶菊(Stevia rebaudian)叶片中一类天然甜味剂,具有高甜度、低热量、无毒副作用等特点,同时还具有一定的药理作用。植物体内主要是通过甲基赤藓糖醇(MEP)途径形成牻牛儿牻牛儿焦磷酸(GGPP),之后该物质在古巴焦磷酸合酶(CPPS)、贝壳杉烯合酶(KS)、贝壳杉烯氧化酶(KO)、糖菊苷转移酶(UGTs)等一系列结构功能各异的酶的作用下最终生成甜菊醇糖苷。SGs生物合成途径的调控及该途径中关键酶的研究已成为目前国内外生物学领域的一大热点。综述了甜叶菊SGs生物合成途径和参与该途径中的关键酶及其基因的研究进展,并展望了其应用前景。

Steviol glycoside is the mixture of natural sweeteners extracted from leaves of Stevia rebaudian （Bertoni） Bertoni, Steviol glycosides have intense sweetness but non-calorific and no toxicity, And steviol glycosides show some degree of pharmacological effects. The precursor ofstevioside, geranylgeranyl pyrophosphate （GGPP）, is formed via the recently discovered 2- C-methyl-d-erythritol-4-phosphate pathway. GGPP is converted to steviol glycosides by a series of enzymes involved copalyl pyrophosphate synthase, kaurene synthase, kaurene acid 13-hydroxylase, UDP-glycosyltransferases et al. This article reviews steviol glycosides biosynthetic pathway of Stevia rebaudian and key enzymes and their research foreground