Chemical transformation of ginsenoside Re by a heteropoly acid investigated using HPLC-MSⁿ/HRMS

Abstract

The mechanism and pathway of heteropoly acid-derived chemical transformation of ginsenoside Re are investigated using multistage tandem mass spectrometry and high-resolution mass spectrometry.

Differentiation and identification of ginsenoside structural isomers by two-dimensional mass spectrometry combined with statistical analysis

“…The curves increased to a maximum at 40 eV and then decreased with CE, indicating that the cleavage of the glycosidic bond at C 3 needs more E int than that of the glycosidic bond at C 20 . This finding is comparable with our previous results that the glycosidic bond at C 3 is less reactive than the one at C 20 in the chemical transformation of ginsenosides [41]. Moreover, the effect of the experimental conditions on the IF and RI distributions were also investigated.…”

“…A boundary line at 25% of IF could be proposed for their differentiation in the CE range from 12–64 eV. The dissociation efficiency of C-K is higher than that of Rh 2 at each CE level, suggesting that the fragmentation of the glycosidic bonds at the C 3 position requires higher E int than does fragmentation at the C 20 position [23], [41]. This behavior is consistent with the results obtained from Rb 2 , Rb 3 , and Rc in the positive ion mode (discussed earlier).…”

“…The latter pathway is considerably more reactive toward deglycosylation. Whereas there is only one approach to produce Y 1β from Rg 3 : fragmentation at the glycosidic bond connecting the disaccharide moiety, which is less reactive than the one at C 20 [41]. In contrast, the order of dissociation efficiency was reversed with regard to the deprotonated aglycone ion at m/z 459 (Fig.…”

“…This indistinguishability was also confirmed by the unpaired t test of their data points and estimated parameters ( p > 0.05, Table S2, Supporting Information). Although the successive cleavage of the glycosidic bond was favored in the negative ion mode and helpful for structural identification [41], the residual charge was solely retained on the aglycone rather than the distinct pentose portion, leading to identical IF distributions. Furthermore, the positive precursor ions normally have higher E int via exothermic association process with alkali metal ions compared with their negative counterparts [39].…”

Simultaneous determination and difference evaluation of 14 ginsenosides in Panax ginseng roots cultivated in different areas and ages by high-performance liquid chromatography coupled with triple quadrupole mass spectrometer in the multiple reaction–monitoring mode combined with multivariate statistical analysis

“…In addition, commercial ginseng products such as red ginseng and black ginseng are normally pharmacologically superior to their original forms due to the rich content of rare ginsenosides [12], [13], [15], [16]. However, rare ginsenosides are scarcely naturally occurring in cultivated ginseng and can be obtained only by the transformation of major ones [17]. Therefore, the accurately quantitative determination of ginsenoside is essential for the assessment of ginseng products and also for the difference evaluation of ginseng samples cultivated in different areas and ages.…”