Kobayashi N, Schmidt J, Wray V, Schliemann W
Abteiling Sekundärstoffwechsel, Leibniz-Institut für Pflanzenbiochemie, Halle (Saale), Germany.
Phytochemistry. 2001 Mar;56(5):429-36. doi: 10.1016/s0031-9422(00)00383-6.
In light of the fact that the main betaxanthin (miraxanthin V) and the major betacyanin (2-descarboxy-betanidin) in hairy root cultures of yellow beet (Beta vulgaris L.) are both dopamine-derived, the occurrence of similar structures for the minor betacyanins was also suggested. By HPLC comparison with the betacyanins obtained by dopamine administration to beet seedlings, enzymatic hydrolysis, LCMS and 1H NMR analyses, the minor betacyanins from hairy roots were identified as 2-descarboxy-betanin and its 6'-O-malonyl derivative. A short-term dopamine administration experiment with fodder beet seedlings revealed that the condensation step between 2-descarboxy-cyclo-Dopa and betalamic acid is the decisive reaction, followed by glucosylation and acylation. From these data a pathway for the biosynthesis of dopamine-derived betalains is proposed. Furthermore, the occurrence of these compounds in various cell and hairy root cultures as well as beet plants (Fodder and Garden Beet Group) is shown.
鉴于黄甜菜（Beta vulgaris L.）毛状根培养物中的主要β-叶黄素（紫黄质V）和主要β-花青素（2-脱羧甜菜色素）均衍生自多巴胺，因此也有人提出次要β-花青素存在类似结构。通过与向甜菜幼苗施用多巴胺所获得的β-花青素进行HPLC比较、酶促水解、LCMS和1H NMR分析，毛状根中的次要β-花青素被鉴定为2-脱羧甜菜红素及其6'-O-丙二酰基衍生物。一项对饲料甜菜幼苗进行的短期多巴胺施用实验表明，2-脱羧环多巴与甜菜醛氨酸之间的缩合步骤是决定性反应，随后是糖基化和酰化反应。根据这些数据，提出了一条多巴胺衍生的甜菜色素生物合成途径。此外，还展示了这些化合物在各种细胞和毛状根培养物以及甜菜植株（饲料甜菜和园用甜菜组）中的存在情况。
