Physicochemical Characterization and NMR Assignments of Ginsenosides Rb₁, Rb₂, R_c, and Rd Isolated from Panax ginseng

Abstract

The fresh ginseng roots were extracted with aqueous methanol, and the obtained extracts were partitioned using ethyl acetate, n-butanol, and water, successively. The repeated silica gel and octadecyl silica gel column chromatogaraphy for n-butanol fraction afforded four diol ginseng saponins, ginsenosides Rb 1 , Rb 2 , Rc, and Rd. The physicochemical, spectroscopic, and chromatographic characteristics of these ginsenosides were measured and compared with those reported in the literature. Some of the peak assignments in previously published 1 H-and 13 C-nuclear magnetic resonance (NMR) spectra were inaccurate. This study employed two-dimensional NMR experiments, including 1 H-1 H correlation spectroscopy, heteronuclear single quantum correlation, and heteronuclear multiple bond connectivity, to determine exact peak assignments.

Development of a method to screen and isolate potential xanthine oxidase inhibitors from Panax japlcus var via ultrafiltration liquid chromatography combined with counter-current chromatography

“…The 1 H and 13 C NMR data are in agreement with those of corresponding compounds in the literature [21][22][23][24][25][26].…”

Metabolomic quality control of commercial Asian ginseng, and cultivated and wild American ginseng using 1H NMR and multi-step PCA

“…Glc = glucose; Ara(p) = alpha-l arabinopyranose, Ara(f) = alpha-L arabinofuranose, Rha = rhamnose. (C) Summary of previous reports[15][16][17] on the 1 H NMR assignments of major ginsenosides. The highlighted ginsenosides are assigned inFig.…”

Discrimination of Panax ginseng Roots Cultivated in Different Areas in Korea Using HPLC-ELSD and Principal Component Analysis

“…All solvents were filtered through 0.45 µm membrane filters before being injected into the HPLC. Ten ginsenosides were isolated and purifi ed from the roots of P. ginseng through a series of chromatography procedures in our laboratory, and their structures were elucidated by comparison of spectroscopic data (IR, MS, 1 H-NMR, and 13 C-NMR) with the literature data: ginsenoside Rh 1 (1) [13]; ginsenoside Rg 2 (2) [13]; ginsenoside Rg 3 (3) [14]; ginsenoside Rg 1 (4) [15]; ginsenoside Rf (5) [16]; ginsenoside Re (6) [16]; ginsenoside Rd (7) [17]; ginsenoside Rb 2 (8) [17]; ginsenoside Rc (9) [17] and ginsenoside Rb1 (10) [18]. The purities of these isolated components were determined to be greater than 98% according to normalization of the peak areas detected via HPLC analysis.…”