Identification of alkaloid constituents from Fangchi species using pH control liquid‐liquid extraction and liquid chromatography coupled to quadrupole time‐of‐flight mass spectrometry

Abstract

The chemical profiling of alkaloids in F. species with different origins was performed for the first time and provided diagnostic ions for diverse alkaloids in F. species. Marker compounds were suggested based on the 28 characterized compounds for quality evaluation and the differentiation of Fangchi species with four different origins.

Identification and metabolite profiling of alkaloids in aerial parts of Papaver rhoeas by liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry

“…As shown in Figure B, the use of moderately acidic additives improved the chromatographic properties when compared to ammonium formate alone. The use of 0.05% formic acid together with the addition of 2.5 mM ammonium formate improved the chromatographic resolution and detection sensitivity of the alkaloids (Figure C), which agrees well with the literature .…”

Identification of Alkaloids in Stephania hainanensis by Liquid Chromatography Coupled with Quadrupole Time‐of‐flight Mass Spectrometry

“…Compound 15 showed an abundant [M + H] + ion at m/z 607.2779. The MS/MS spectrum of it was consistent with that of cepharanthine in the literature (Sim et al , ), and the results showed a dimeric isoquinoline fragment at m/z 380.1709 and its demethylated ion at m/z 365.1439, single isoquinoline fragments at m/z 192.1005 and 190.0851 and a diphenyl ether moiety at m/z 227.1058. Other fragments at m/z 576.2396 and 564.2350, which were formed by the losses of NH 2 CH 3 and C 2 H 5 N from the [M + H] + ion, respectively, were also observed.…”

“…Both of the ions at m/z 297.1126 and 237.0915 could further eliminate the peripheral groups including CH 3 , OCH 3 and H 2 O. The ions discussed earlier followed the general rules in the literature (Stévigny et al , ; Sim et al , ). Another parallel pathway observed was loss of CH 3 N = CH 2 ( m/z 299.1293) followed by eliminations of the peripheral groups.…”

“…The dimeric isoquinoline fragment ion could further split to form the single isoquinoline fragments at m/z 192.1023 and 176.1065. The characteristic ions [M + H–NH 2 CH 3 ] + and [M + H–C 2 H 5 N] + were also observed in the MS/MS spectrum (Wu and Moyer, ; Sim et al , ).…”

“…Compound 1 was assumed to be a benzylisoquinoline alkaloid with a hexose based on the diagnostic ion [M + H–162] + . The exact mass ( m/z 448.1967) of compound 1 was consistent with that of O 6 ‐methylhigenamine‐7‐ O‐β ‐D‐glucopyranoside, which has been reported in Stephania plants (Sim et al , ). The successive losses of NH 3 ( m/z 269.1173) and CH 3 OH ( m/z 237.0900) from the ion [M + H–162] + ( m/z 286.1438), the benzylic cleavage fragment at m/z 107.0484 and the fragment at m/z 175.0748 supported the identification (Semwal et al , ; Sim et al , ).…”