Determination of the chemical constituents of the different processed products of Anemarrhena asphodeloides Rhizomes by high‐performance liquid chromatography quadrupole time‐of‐flight mass spectrometry

Abstract

In this work, high-performance liquid chromatography (HPLC) coupled with a hybrid quadrupole time of-flight mass spectrometry (Q-TOF-MS/MS) was used to study chemical compositions of different processed products of Rhizoma Anemarrhenae (RA). A Grace Alltima(TM) C18 column (250 × 4.6 mm, 5 µm) was used for separation. Mobile phase consisted of 0.1% formic acid and acetonitrile, using gradient elution. ESI-MS data was acquired in both positive and negative mode. The experiment was established on the basis of a series of reference substances (two xanthone and seven saponins) to qualitatively identify the chemical compounds of different processed products of RA by MS analysis. There was no difference in the type of chemical constituents between different processed products of RA. A total of 25 compounds were identified, including four xanthones, 21 steroidal saponins and eight pairs of isomers.

Rapid Screening of Chemical Constituents in Rhizoma Anemarrhenae by UPLC‐Q‐TOF/MS Combined with Data Postprocessing Techniques

“…According to CFs and NLs rules shown in Table 1, compound 29 was revealed as spirostanol saponins (type I). These results are consistent with the fragmentation pathway of timosaponin AIII [5, 27]. A proposed mechanistic pathway for fragments formed in MS is shown in Figure 3.…”

“…The fragment ion at m/z 1211 [M-H-H 2 O] − indicated the presence of hydroxyl at the position of C-22 due to the fact that furostanol glycosides preferentially lose hydroxyl located in C-22. Compound 8 can be identified as purpureagitoside through comparison with the literature [5, 27]. The fragmentation patterns of purpureagitoside are presented in Figure 2.…”

“…All steroidal saponins produce abundant characteristic fragment ions through the loss of the branched glycoside chains and side chains or by dehydration; the ions could be rapidly identified by combining CFs with NLs at m/z 162 (C 6 H 10 O 5 ), 132 (C 5 H 8 O 4 ), 142 (C 8 H 14 O 2 ) and 18 (H 2 O). We used compounds purpureagitoside, timosaponin H1, and timosaponin AIII to discuss the fragmentation pathways in detail in the successive ESI–MS n experiments [5, 23, 24, 27, 30]. …”

“…The fragment ion at m/z 271 [M-H-H 2 O-C 5 H 8 O 4 -4C 6 H 10 O 5 -C 8 H 14 O 2 ] − was produced by the losses of sugar chains and side chains only. Thus, compound 13 was identified as timosaponin H1 [5, 27]. …”

“…This TCM is the dried rhizome of the Liliaceae Anemarrhena genus and has been widely used for clinical treatment of febrile disease, high fever and thirst, cough and asthma, osteopyrexia and fever, and other diseases [1, 2]. The pharmacologically active components of Rhizoma Anemarrhenae include steroidal saponins, flavonoids, phenylpropanoids, alkaloids, and benzophenones, with saponins being the major constituents [3–5]. At present, the analytical methods of TCM ingredients mainly include thin layer chromatography (TLC), gas chromatography (GC), high-performance liquid chromatography (HPLC), and ultraperformance liquid chromatography/time-of-flight mass spectrometry (UPLC-Q-TOF/MS), among others.…”