Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand.
Natural Products Laboratory, Institute of Biology, Leiden University,55 Einsteinweg, 2300 RA Leiden, The Netherlands.
Z Naturforsch C J Biosci. 2013 Sep-Oct;68(9-10):394-405.
Metabolite profiles of Mitragyna speciosa were determined by means of 1H NMR-based and HPLC-based analyses. The results indicated that high contents of secologanin, caffeic acid, gallic acid, epigallocatechin, and mitragynine were accumulated in leaves. In M. speciosa, feedings of tryptamine, tryptophan, phenylalanine or tyrosine significantly increased the mitragynine contents. Feedings of tryptamine and loganin also enhanced the mitragynine accumulation, but feeding of loganin only did not affect the mitragynine level. The mRNA levels of anthranilate synthase alpha subunit (ASA), tryptophan decarboxylase (TDC), and strictosidine synthase (STR) were measured by quantitative real-time polymerase chain reaction (RT-qPCR) in control plants and those exposed to methyl jasmonate (MJ; 10 microM). All genes responded to MJ after a 24-h treatment. The mitragynine contents were also enhanced and corresponded to the transcript levels. From the present results we conclude that a high content of secologanin together with a undetectable level of tryptamine in M. speciosa feature the limitation of mitragynine biosynthesis. Additionally, expression of all the genes limits production of an essential precursor for mitragynine production.
利用基于 1H NMR 和 HPLC 的分析方法确定了小花牡荆的代谢产物谱。结果表明，叶子中积累了大量的蛇麻酮、咖啡酸、没食子酸、表儿茶素和醉茄碱。在小花牡荆中，色胺、色氨酸、苯丙氨酸或酪氨酸的喂养显著增加了醉茄碱的含量。色胺和蛇麻酮的喂养也增强了醉茄碱的积累，但蛇麻酮的喂养并不影响醉茄碱的水平。通过定量实时聚合酶链反应 (RT-qPCR) 在对照植物和暴露于茉莉酸甲酯 (MJ; 10 microM) 的植物中测量了邻氨基苯甲酸合酶 α 亚基 (ASA)、色氨酸脱羧酶 (TDC) 和斯梯罗苷合酶 (STR) 的 mRNA 水平。所有基因在 24 小时处理后均对 MJ 产生反应。醉茄碱的含量也得到了提高，并与转录水平相对应。从目前的结果我们得出结论，小花牡荆中蛇麻酮含量高，而色胺含量检测不到，这是醉茄碱生物合成的限制因素。此外，所有基因的表达限制了醉茄碱生产的必需前体的产生。
