Jilin Provincial Key Laboratory of Chinese Medicine Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
Institute of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230029, China.
Molecules. 2022 Jul 4;27(13):4302. doi: 10.3390/molecules27134302.
L. (PAL) as a medicinal and edible plant is rich in chemical compounds, which makes the systematic and comprehensive characterization of its components challenging. In this study, an integrated strategy based on three-dimensional separation including AB-8 macroporous resin column chromatography, ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF MS), and ultra-high performance liquid chromatography-mass spectrometry with ion-mobility spectrometry (UHPLC-IM-MS) was established and used to separate and identify the structures of compounds from PAL. The extracts of PAL were firstly separated into three parts by AB-8 macroporous resin and further separated and identified by UHPLC-Q-TOF MS and UHPLC-IM-MS, respectively. Additionally, UHPLC-IM-MS was used to identify isomers and coeluting compounds, so that the product ions appearing at the same retention time (RT)can clearly distinguish where the parent ion belongs by their different drift times. UNIFI software was used for data processing and structure identification. A total of 86 compounds, including triterpenes, iridoids, phenylethanoid glycosides, guanidine derivatives, organic acids, and fatty acids, were identified by using MS information and fragment ion information provided by UHPLC-Q-TOF MS and UHPLC-IM-MS. In particular, a pair of isoforms of plantagoside from PAL were detected and identified by UHPLC-IM-MS combined with the theoretical calculation method for the first time. In conclusion, the AB-8 macroporous resin column chromatography can separate the main compounds of PAL and enrich the trace compounds. Combining UHPLC-IM-MS and UHPLC-Q-TOF MS can obtain not only more fragments but also their unique drift times and RT, which is more conducive to the identification of complex systems, especially isomers. This proposed strategy can provide an effective method to separate and identify chemical components, and distinguish isomers in the complex system of traditional Chinese medicine (TCM).
作为药用和食用植物，蒲公英含有丰富的化学成分，这使得对其成分进行系统和全面的特征描述具有挑战性。在这项研究中，建立了一种基于三维分离的综合策略，包括 AB-8 大孔树脂柱色谱、超高效液相色谱-四极杆飞行时间质谱（UHPLC-Q-TOF MS）和带有离子迁移谱的超高效液相色谱-质谱（UHPLC-IM-MS），用于分离和鉴定蒲公英化合物的结构。首先，通过 AB-8 大孔树脂将蒲公英提取物分离成三部分，然后分别通过 UHPLC-Q-TOF MS 和 UHPLC-IM-MS 进行分离和鉴定。此外，UHPLC-IM-MS 用于鉴定异构体和共洗脱化合物，因此，在相同保留时间（RT）下出现的产物离子可以通过其不同的漂移时间清楚地区分母离子所属的位置。UNIFI 软件用于数据处理和结构鉴定。共鉴定出 86 种化合物，包括三萜、环烯醚萜、苯乙醇苷、胍衍生物、有机酸和脂肪酸，这些化合物的结构是通过 UHPLC-Q-TOF MS 和 UHPLC-IM-MS 提供的 MS 信息和碎片离子信息来确定的。特别是，首次通过 UHPLC-IM-MS 结合理论计算方法检测并鉴定了蒲公英中的一对植物甾醇异构体。总之，AB-8 大孔树脂柱色谱可以分离蒲公英的主要化合物并富集痕量化合物。结合 UHPLC-IM-MS 和 UHPLC-Q-TOF MS 不仅可以获得更多的片段，还可以获得其独特的漂移时间和 RT，这更有利于复杂体系，特别是异构体的鉴定。该策略可以为分离和鉴定中药复杂体系中的化学成分以及区分异构体提供有效的方法。
