Laboratory of Natural Compounds Chemistry and Bioanalytics, Core Facility Center "Arktika", M.V. Lomonosov Northern (Arctic) Federal University, Northern Dvina Emb. 17, 163002 Arkhangelsk, Russia.
Molecules. 2023 May 7;28(9):3945. doi: 10.3390/molecules28093945.
Pentacyclic triterpenoids (PCTs), which possess a number of bioactive properties, are considered one of the most important classes of secondary plant metabolites. Their chromatographic determination in plant biomass is complicated by the need to separate a large number of structurally similar compounds belonging to several classes that differ greatly in polarity (monools, diols, and triterpenic acids). This study proposes a rapid, sensitive, and low-cost method for the simultaneous quantification of ten PCTs (3-taraxerol, lupeol, -amyrin, -amyrin, betulin, erythrodiol, uvaol, betulinic, oleanolic, and ursolic acids) by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) using porous graphitic carbon (Hypercarb) as a stationary phase capable of hydrophobic retention and specific interactions with analytes. Revealing the effects of the mobile phase composition, pH, ionic strength, and column temperature on retention and selection of chromatographic conditions on this basis allowed for the effective separation of all target analytes within 8 min in gradient elution mode and attaining limits of detection in the range of 4-10 µg L. The developed method was fully validated and successfully tested in the determination of PCTs in common haircap () and prairie sphagnum () mosses, and fireweed () stems and leaves.
五环三萜类化合物（PCTs）具有多种生物活性，被认为是最重要的次生植物代谢物类别之一。由于需要分离属于几个类别的大量结构相似的化合物，这些化合物在极性方面差异很大（单醇、二醇和三萜酸），因此在植物生物量中对其进行色谱测定变得复杂。本研究提出了一种快速、灵敏、低成本的方法，通过高效液相色谱-串联质谱（HPLC-MS/MS）同时定量分析十种五环三萜类化合物（蒲公英萜醇、羽扇豆醇、α-香树脂醇、β-香树脂醇、桦木醇、赤藓醇、乌苏酸、齐墩果酸、熊果酸），使用多孔石墨碳（Hypercarb）作为固定相，能够进行疏水保留和与分析物的特异性相互作用。揭示流动相组成、pH 值、离子强度和柱温对保留和色谱条件选择的影响，在此基础上，能够在梯度洗脱模式下在 8 分钟内有效分离所有目标分析物，并在 4-10 µg L 的范围内达到检测限。该方法已充分验证，并成功应用于普通羊胡子草（）和泥炭藓（）苔藓以及柳兰（）茎叶中五环三萜类化合物的测定。
