Re-evaluation of physicochemical and NMR data of triol ginsenosides Re, Rf, Rg2, and 20-gluco-Rf from Panax ginseng roots

Abstract

Ginseng roots were extracted with aqueous methanol, and extracts were suspended in water and extracted successively with ethyl acetate and n-butanol. Column chromatography using the n-butanol fraction yielded four purified triol ginseng saponins: the ginsenosides Re, Rf, Rg2, and 20-gluco-Rf. The physicochemical, spectroscopic, and chromatographic characteristics of the ginsenosides were measured and compared with reports from the literature. For spectroscopic analysis, two-dimensional nuclear magnetic resonance (NMR) methods such as 1H-1H correlation spectroscopy, nuclear Overhauser effect spectroscopy, heteronuclear single quantum correlation, and heteronuclear multiple bond connectivity were employed to identify exact peak assignments. Some peak assignments for previously published 1H- and 13C-NMR spectra were found to be inaccurate. This study reports the complete NMR assignment of 20-gluco-Rf for the first time.

Complete 1H-NMR and 13C-NMR spectral assignment of five malonyl ginsenosides from the fresh flower buds of Panax ginseng

“…The 13 C-NMR (Table 2) spectrum showed 51 carbon signals, including a pair of olefinic carbons at C-24 ( δ c 126.501) and C-25 ( δ c 131.495), two oxygen-substituted carbons at C-6 ( δ c 75.122) and C-20 ( δ c 83.925), and two carbonyl-group signals at C-M1 ( δ c 169.308) and C-M3 ( δ c 171.075). These data suggest that compound 1 was a dammarane-type triterpene glycoside with a double bond and a malonyl group [15], [16], [17], [18]. The chemical structure of compound 1 was further elucidated by a HMBC (Figure 2) experiment in which correlations were observed between H-1′ ( δ H 5.22, d, J  = 6.8 Hz ) and the carbon resonance signal at C-6 ( δ c 75.122 ), H-1′′ ( δ H 6.46, brs ) and C-2′ ( δ c 79.083 ), and H-1‴ ( δ H 5.04, d, J = 7.7 Hz ) and C-20 ( δ c 83.925 ), which indicated that the C-1 Glc′ , C-1 Glc′′ , and C-1 Rha′′′ were linked to C-6, C-2′, and C-20, respectively.…”

“…Other carbon shifts included an upfield shift of C-5‴ ( δ C 75.389) and a downfield shift of C-6‴ ( δ C 65.755), as compared to ginsenoside Re [15], [16]. H-5‴ yielded a peak at 3.96, and H-6‴ at 4.98 and 4.71, based on the HSQC spectrum.…”

Effects of extrusion conditions on chemical properties of extruded white ginseng root hair

“…Sun reported the total saponin content in ginseng root hair as being higher than that in other parts of ginseng. Ginseng has drawn attention as a traditional medicine worldwide because of its various functions, such as anti‐diabetes, anti‐inflammatory, antioxidant and anticancer activities …”

“…Ginseng has drawn attention as a traditional medicine worldwide because of its various functions, such as anti-diabetes, anti-inflammatory, antioxidant and anticancer activities. [5][6][7][8][9][10][11][12][13] Baek et al 14 reported that heat processing led to chemical and structural changes, improving the biological activities. Extrusion has been considered as a high-temperature short-time process to produce commercial products for over 50 years, because of its high productivity, energy efficiency and versatility.…”

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.…”