Repetitious steaming-induced chemical transformations and global quality of black ginseng derived from Panax ginseng by HPLC-ESI-MS/MSn based chemical profiling approach

Abstract

A high performance liquid chromatographyelectrospray tandem mass spectrometry (HPLC-ESI-MS/ MS n ) based chemical profiling method was developed to evaluate repetitious steaming-induced chemical transformations in black ginseng (BG and Korean white ginseng subjected to nine cycles of steam treatment). Under the optimized HPLC and ESI-MS/MS n conditions, more than 13 and 17 peaks were separated and detected in white ginseng (WG) and BG within 85 min, respectively. The components were identified by comparing the mass spectrum and/or matching the empirical molecular formula with that of known published compounds. In total, 17 major ginsenosides were identified in BG, 16 of which were determined to be newly generated during the BG preparatory process. The mechanisms involved were further deduced to be hydrolysis, dehydration, isomerization, and decarboxylation reactions of the original ginsenosides in WG by analyzing nine mimic cycles of steaming extracts of seven pure reference ginsenosides. A significant difference in chemical profiles between BGs developed from two batches of WG suggested that storage duration significantly influenced the quality consistency of not only the crude drug but also the BG derived from WG.

UPLC-Q-TOF-MS/MS Analysis for Steaming Times-dependent Profiling of Steamed Panax quinquefolius and Its Ginsenosides Transformations Induced by Repetitious Steaming

“…3F) and was identified as Rh 3 . The mechanisms involved were deduced to be the loss of glycosyl moiety at C-20-OH of Rb1, Rb2, Rc and Rd through hydrolysis to generate 20( S )-Rg3, then 20( S )-Rg3 further underwent dehydration to generate ginsenosides Rk1 and Rg5, or eliminated the terminal glycosyl moiety at C-3 position to generate ginsenoside Rh2, which was consistent with our previous findings [16,18]. Subsequently, ginsenosides Rh3 and Rk2 were further generated through dehydration at C-20 of Rh2 and elimination the terminal glycosyl moiety at C-3 of Rk1 respectively.…”

“…It should be noted that 20( R )-Rg3 is detected in multi-steamed P. quinquefolius and mimic 9 cycles of steaming extracts of ginsenoside Rb1, Rb2, Rc, and Rd, and its peak area and height always are less than those of 20( S )-Rg3 (Figs. 2B-D and 3A-D), which was similar with the finding reported by the references [18,38]. No naturally occurring 20( R )-ginsenosides have reported so far, therefore 20( R )- Rg3 was assumed to be generated from Rk1 or Rg5 via addition reaction.…”

“…3A-D), and were identified as 20( S )-Rg3, 20( R )-Rg3, Rk1, Rg5, Rh2, Rk2, and Rh3, respectively [18,37]. Similarly, the abovementioned seven peaks (peaks 14-17, 19, 28, and 29) was also detected in the mimic 9 cycles of steaming extracts of ginsenosides 20 ( S )-Rg3 (Fig.…”

“…may also affect the chemical profiles of ginseng. With the comparison of ginsengs steamed for 2 to 3 times, dried by sunlight [16-18,35] or puffed by high pressure [36], ginsengs undergone 9 cycles of steaming undoubtedly possessed more ginsenosides of low polarity. What’s more, the starch molecules in the ginseng tissue were gradually changed from sol state to gel state in the BAG preparatory process, which made BAG easier to be absorbed by human body.…”

“…Among them, black ginseng is developed from raw P. ginseng by nine-time steaming at 98℃ for 3 h and nine-time drying [12,13], at which point it becomes black in color [14,15], while black American ginseng (BAG, American ginseng that was subjected to 9 cycles of steaming treatment) is still unreported to date. Nine-time steaming and nine-time drying is frequently used for preparing modified or processed Chinese herbal medicines (e.g., Rehmanniae radix Preparata, Polygonatum sibiricum Red., P. ginseng Meyer and Arisaema heterophyllum Blume) so as to reinforce its pharmacological activity, to attenuate its adverse response, to improve the stability or to change its medicinal effects, etc., but studies on the holistic chemical profiles of multi-steamed Chinese herbal medicines were attempted only in recently years [16-18].…”