Man Shuli, Gao Wenyuan, Zhang Yanjun, Jin Xinghua, Ma Chaoyi, Huang Xianxiao, Li Qingyun
School of Pharmaceutical Science and Technology, Tianjin University, Weijin Road, Tianjin, 300072, China.
Anal Bioanal Chem. 2009 Sep;395(2):495-505. doi: 10.1007/s00216-009-2987-2. Epub 2009 Aug 6.
Rhizoma Paridis saponins are bioactive steroidal saponins derived from Paris polyphylla. Optimization of the ionization process was performed with electrospray ionization tandem mass spectrometry in both positive and negative-ion modes. Negative-ion ESI was adopted for generation of the precursor deprotonated molecules to achieve the best ionization sensitivity for the analytes. Positive ionization was used to choose the most abundant fragment ion. Furthermore, according to the characteristic fragmentation behavior of known steroidal saponins isolated from this plant (polyphyllin D, formosanin C, gracillin, Paris H, Paris VII, and dioscin), 23 constituents were structurally characterized on the basis of their retention time and ESI analyses, including four pairs of naturally occurring isomers. Five of these 23 constituents were new compounds. The analytical method of LC-MS(n) in positive and negative-ion modes has been developed for the direct structural elucidation of steroid saponins of this kind in plant extracts.
重楼皂苷是从七叶一枝花中提取的具有生物活性的甾体皂苷。采用电喷雾电离串联质谱法在正离子和负离子模式下对电离过程进行优化。负离子电喷雾电离用于生成前体去质子化分子，以实现对分析物的最佳电离灵敏度。正离子电离用于选择最丰富的碎片离子。此外，根据从该植物中分离出的已知甾体皂苷（多叶皂苷D、金线重楼皂苷C、偏诺皂苷元、重楼皂苷H、重楼皂苷VII和薯蓣皂苷）的特征裂解行为，基于保留时间和电喷雾电离分析对23种成分进行了结构表征，包括四对天然存在的异构体。这23种成分中有5种是新化合物。已开发出正离子和负离子模式下的液相色谱-质谱(n)分析方法，用于直接阐明植物提取物中此类甾体皂苷的结构。
