Biosynthesis of Vanillin via Ferulic Acid in Vanilla planifolia
Biosynthesis of Vanillin via Ferulic Acid in Vanilla planifolia
复制标题
DOI：
10.1021/jf901204m
复制
发表时间：
2009-11-11
影响因子：
6.1
通讯作者：
Negishi, Yukiko
中科院分区：
文献类型：
--
作者：
Negishi, Osamu;Sugiura, Kenji;Negishi, Yukiko
(14)将C标记的苯丙氨酸、4-香豆酸、4-羟基苯甲醛、4-羟基苯甲醇、阿魏酸和蛋氨酸分别应用于授粉后3个月和6个月的绿色香草果的圆盘上，研究这些化合物转化为香草醛或葡萄糖醛的反应。在成熟的绿色香草荚中，~(14)C标记的苯丙氨酸、4-香豆酸、阿魏酸和蛋氨酸的放射性活度分别为11%、15%、29%和24%。然而，(14)C标记的4-羟基苯甲醛和4-羟基苯甲醇不能转化为葡香兰素。另一方面，在未成熟的绿色香草豆荚中，上述六种化合物的放射性没有被掺入葡甘香兰素中。虽然4-香豆酸、阿魏酸、4-羟基苯甲醛和4-羟基苯甲醇分别转化为葡萄糖酯或糖苷，香草醛转化为葡萄糖醛，但它们的转化被认为是通过苷元的解毒完成的。这些结果表明，香草醛在成熟的香草荚中的生物合成途径是4-香豆酸->；->；阿魏酸->；->；香草醛->；葡萄糖醛。
(14)C-Labeled phenylalanine, 4-coumaric acid, 4-hydroxybenzaldehyde, 4-hydroxybenzyl alcohol, ferulic acid, and methionine were applied to disks of green vanilla pods 3 and 6 months after pollination (immature and mature pods), and the conversion of these compounds to vanillin or glucovanillin was investigated. In mature green vanilla pods, radioactivities of 11, 15, 29, and 24% from (14)C-Iabeled phenylalanine, 4-coumaric acid, ferulic acid, and methionine, respectively, were incorporated into glucovanillin within 24 h. In the incorporation processes of methionine and phenylalanine into glucovanillin, some of the (14)C labels were also trapped by the unlabeled ferulic acid. However, (14)C-labeled 4-hydroxybenzaldehyde and 4-hydroxybenzyl alcohol were not converted to glucovanillin. On the other hand, in immature green vanilla pods radioactivities of the above six compounds were not incorporated into glucovanillin. Although 4-coumaric acid, ferulic acid, 4-hydroxybenzaidehyde, and 4-hydroxybenzyl alcohol were converted to the respective glucose esters or glucosides and vanillin was converted to glucovanillin, their conversions were believed to be from the detoxication of the aglycones. These results suggest that the biosynthetic pathway for vanillin is 4-coumaric acid -> -> ferulic acid -> -> vanillin -> glucovanillin in mature vanilla pods.