Plant Product and Food Quality Department, Scottish Crop Research Institute, Invergowrie Dundee, United Kingdom.
Planta Med. 2011 Feb;77(3):293-300. doi: 10.1055/s-0030-1250314. Epub 2010 Sep 15.
Pilocarpine is an imidazole alkaloid that has been used for more than a century in glaucoma treatment. It is present in several species of the Pilocarpus genus (jaborandi), with its highest concentrations in P. microphyllus. In addition to pilocarpine, pilosine--an imidazole alkaloid without pharmacological use--is produced in high concentrations in mature plants. A metabolomic study was carried out on juvenile and mature plants to obtain information about pilocarpine metabolism at different developmental stages. Methanol-water and alkaloid extracts were analyzed by ¹H NMR and ESI-MS. Metabolic profiles from both techniques showed clear differences between various developmental stages. Intense signals in the aromatic region of the ¹H NMR spectrum and ions from pilosine and related alkaloids by ESI/MS were found only in extracts from mature plant. Two new imidazole alkaloids were identified by MS(n). Our results suggest that pilosine is produced exclusively in mature developmental stage, and juvenile plant material seems to be appropriate for further studies on pilocarpine biosynthesis.
毛果芸香碱是一种咪唑类生物碱，在青光眼治疗中已经使用了一个多世纪。它存在于几种月橘属（假鹰爪属）植物中，其中含量最高的是小毛果芸香。除了毛果芸香碱外，成熟植物中还会产生高浓度的无药理作用的咪唑类生物碱——pilosine。对幼年和成年植物进行代谢组学研究，以获得不同发育阶段毛果芸香碱代谢的信息。采用¹H NMR 和 ESI-MS 对甲醇-水和生物碱提取物进行分析。两种技术的代谢谱在不同的发育阶段都表现出明显的差异。¹H NMR 光谱的芳香区中的强信号和 ESI/MS 中的 pilosine 和相关生物碱的离子仅存在于成熟植物的提取物中。通过 MS(n) 鉴定出两种新的咪唑类生物碱。我们的研究结果表明，pilo sine 仅在成熟的发育阶段产生，而幼年植物材料似乎适合进一步研究毛果芸香碱的生物合成。
