Characterization and identification of steroidal alkaloids in the Chinese herb Veratrum nigrum L. by high‐performance liquid chromatography/electrospray ionization with multi‐stage mass spectrometry

Abstract

Electrospray ionization multi-stage mass spectrometry (ESI-MS(n)) was performed to study the fragmentation behaviour of seventeen steroidal alkaloids (4 protoverine-type alkaloids, 10 germine-type alkaloids and 3 zygadenin-type alkaloids) from the Chinese herb Veratrum nigrum L. The MS(n) spectra of the [M+H](+) ions for steroidal alkaloids provided a wealth of structural information on the substituted groups. In positive ion mode, the three types of alkaloids showed very different characteristic ions: m/z 436 or 418 for protoverine-type alkaloids; m/z 438, 420 or 402 for germine-type alkaloids; m/z 440 or 422 for zygadenin-type alkaloids. These fragments were used to deduce their mass spectral fragmentation mechanisms. Furthermore, the primary compounds in methanolic extracts of the herb of Veratrum nigrum L. were investigated by using liquid chromatography (LC)/ESI-MS(n). As a result, 21 steroidal alkaloids (5 protoverine-type alkaloids, 14 germine-type alkaloids and 2 zygadenin-type alkaloids) were selectively identified from 27 determined peaks. Eleven compounds were unambiguously identified by comparing with standard compounds and ten compounds were tentatively identified or deduced according to their MS(n) data. Two of these compounds (xingangermine and deacetyl xinganveratrine) were found to be novel steroidal alkaloids. In addition, the chemical structures of two pairs of steroidal alkaloid isomers were deduced by comparing their fragment ions. Given the important structural information of known and unknown steroidal alkaloids in crude herbal extracts, this study is useful for identifying these types of steroidal alkaloids in crude materials rapidly and selectively.

Characterization and identification of steroidal alkaloids in Fritillaria species using liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry

“…Recently, LC/ion trap multistage mass spectrometry (IT-MS n ) and/or LC/triplequadrupole MS have been successfully applied to the identification and characterization of natural compounds [14,15]. For example, Li et al have reported on detailed studies of the fragmentation behaviors of 17 steroidal alkaloids from the Chinese herb Veratrum nigrum L. (Veratrum alkaloids) by LC-ESI-IT-MS n [16]. Nevertheless, in most studies using low-resolution MS instruments, such as IT-MS and triple-quadrupole MS, it is difficult to confirm the identities of the product ions.…”

Metabolomics Study of Cultivated Bulbus Fritillariae Cirrhosae at Different Growth Stages using UHPLC‐QTOF‐MS Coupled with Multivariate Data Analysis

“…Metabolomic approaches, especially liquid chromatography mass spectrometry (LC–MS)‐based metabolomic approaches, have been proven successful in qualitative evaluations of traditional Chinese medicine (Li et al ., ; Gao et al ., ; Sun et al ., ; Zhang et al ., ) due to high sensitivity and ability to provide structural information of rare metabolites. LC–MS allows sufficient separation and detection of semipolar metabolites, often characteristic of plant secondary metabolites (Li et al ., ; Zhu et al ., ; Zhou, Han, Song, Qiao, & Xu, ). A metabolomics approach to characterise global changes of metabolites (Want, Cravatt, & Siuzdak, ; Nordstrom, Maille, Qin, & Siuzdak, ) was adopted to investigate chemical variation in BFC.…”

Biotransformation of Vermitaline by Cunninghamella echinulata

“…In continuation of our studies on the phytochemistry of Veratrum alkaloids [14] [15], we now report the characterization of four metabolites of vermitaline (1) in cell suspension of C. echinulata (ACCC 30369). The metabolites, which were more polar than 1, were identified as 7a-hydroxyrubijervine (2) (22)), and 61.6 (C(26)), which are characteristic for a solanidine type steroid alkaloid.…”