Data Acquisition Strategy for Mass Spectrometers Applied to Bottom-up-Based Protein Identification

Global identification and determination of the major constituents in Kai-Xin-San by ultra-performance liquid chromatography-quadrupole-Orbitrap mass spectrometry and gas chromatography-mass spectrometry

Kai-Xin-San (KXS) is a traditional Chinese medicine (TCM) formula containing four herbal medicines: Ginseng Radix Rhizoma, Polygalae Radix, Poria and Acori Tatarinowii Rhizoma. A large number of pharmacological studies in vitro and in vivo have shown that KXS is characterized by anti-depression, anti-Alzheimer's disease, anti-oxidation and other activities. However, the pharmacodynamic substance basis studies of KXS are hitherto quite limited. Here, KXS was identified and determined by ultra-performance liquid chromatography-quadrupole-Orbitrap mass spectrometry (UPLC-Q-Orbitrap MS) and gas chromatography-mass spectrometry (GC-MS). Firstly, the data-dependent acquisition mode (DDA) of UPLC-Q-Orbitrap MS combined with the inclusion list were used to collected the chemical composition. The chemical constituents of KXS were identified by local database on compound discoverer™ 3.1 software and Xcalibur 4.1 software. With the use of this approach, a total of 211 compounds were identified from KXS. Wherein 60 compounds were from Ginseng Radix Rhizoma, 40 compounds were from Poria, and 111 compounds were from Polygala Radix, respectively. Secondly, 105 volatile constituents were identified by GC-MS analysis, which were mainly derived from Acori Tatarinowii Rhizoma. Besides, an adjusted parallel reaction monitoring method was established and validated to quantify the seventeen major compounds in different herbal medicines of KXS, which were chosen as the benchmarked substances to evaluate the quality of KXS. In conclusion, this study provided a generally applicable strategy for global metabolite identification of the complicated components and determination of multi-component content in traditional Chinese medicines.