A reversed-phase high-performance liquid chromatography method with pulsed amperometric detection for the determination of glycosides

Simultaneous quantification method for eleutheroside B, eleutheroside E, chiisanoside, and sesamin using reverse-phase high-performance liquid chromatography coupled with ultraviolet detection and integrated pulsed amperometric detection

We developed a method combining ultraviolet (UV) detection and integrated pulsed amperometric detection (IPAD) to simultaneously analyze eleutheroside B, eleutheroside E, chiisanoside, and sesamin. The gradient elution system allowed complete separation of all target components within 35 min, and showed limits of detection of 0.006-0.020 μg/mL and limits of quantification of 0.018-0.050 μg/mL. The linear regression coefficients of determination were 0.9990-0.9998. All inter- and intra-day precision values were below 4.89%, and the average recoveries were 97.79-104.40%. The developed approach exhibits excellent reproducibility, sensitivity, and selectivity without requiring any complicated pre-treatment, and is therefore expected to be helpful as a tool for establishing appropriate content criteria for Acanthopanax species.

Simultaneous quantification of six nonpolar ginsenosides in white ginseng by reverse-phase high-performance liquid chromatography coupled with integrated pulsed amperometric detection

Background

White ginseng consists of the roots and rhizomes of the Panax species, and red ginseng is made by steaming and drying white ginseng. While red ginseng has both polar and nonpolar ginsenosides, previous studies showed white ginseng to have only polar ginsenosides. Because nonpolar ginsenosides are formed through the manufacture of red ginseng from white ginseng, researchers have generally thought that nonpolar ginsenosides do not exist in white ginseng.

Methods

We developed a simultaneous quantitative method for six nonpolar ginsenosides in white ginseng using reverse-phase high-performance liquid chromatography coupled with integrated pulsed amperometric detection. The nonpolar ginsenosides of white ginseng were extracted for 4 h under reflux with 50% methanol.

Results

Using the gradient elution system, all target components were completely separated within 50 min. Nonpolar ginsenosides were determined in the rhizome head (RH), main root (MR), lateral root, and hairy root (HR) of 6-year-old white ginseng samples obtained from several regions (Geumsan, Punggi, and Kanghwa). The total content in the HR of white ginseng was 37.8–56.8% of that in the HR of red ginseng. The total content in the MR of white ginseng was 5.9–24.3% of that in the MR of red ginseng. In addition, the total content in the RH of white ginseng was 28.5–35.8% of that in the HR of red ginseng

Conclusion

It was confirmed that nonpolar ginsenosides known to be specific components of red ginseng were present at substantial concentrations in the HR or RH of white ginseng.

Method development for the certification of a ginsenoside calibration solution via liquid chromatography with absorbance and mass spectrometric detection

The research presented here describes the development of two analytical methods for use in the certification of a ginsenoside calibration solution Standard Reference Material (SRM) 3389 consisting of seven ginsenosides: Rg1, Re, Rf, Rb1, Rc, Rb2, and Rd. The new methods utilized the liquid chromatographic (LC) separation of ginsenoside mixtures with absorbance detection (UV) and mass spectrometry (MS). Ginsenosides Rb3, Rg2, Rg3, Rh1, and Rh2 were evaluated for use as internal standards for LC/MS measurements. The 12 ginsenosides were baseline resolved by gradient elution LC/UV, with an initial mobile phase composition of 22% acetonitrile and 78% water, flow rate of 0.7 mL/min, and column temperature of 25 °C. The work presented here includes a detailed investigation into the optimization of the chromatographic conditions to minimize measurement biases that result from unresolved constituents. Temperature and mobile phase composition are known to play a significant role in column selectivity; however, flow rate is expected to influence primarily the separation efficiency and detection sensitivity. In the current study, column selectivity changed with changes in flow rate and the relative retention of ginsenoside Rg2 and Rh1 changed as the flow rate increased from 0.6 mL/min to 1.0 mL/min.

Quantification of isoflavonoids and triterpene saponins in Astragali Radix, the root of Astragalus membranaceus, via reverse-phase high-performance liquid chromatography coupled with integrated pulsed amperometric detection

Astragali Radix, the root of Astragalus membranaceus Bunge, is one of the most frequently used crude drugs in Asian medicine. We developed a quantification method for 6 components (calycosin, formononetin, astragaloside I-IV) of Astragali Radix and Hwanggi-gyeji-omul-tang (HGOT) using reverse-phase high-performance liquid chromatography coupled with integrated pulsed amperometric detection (RP-HPLC-IPAD). The plants were extracted in 80% ethanol for 2h. All target components were detected with good sensitivity using sodium hydroxide (as a post-column eluent). The limit of detection (S/N=3) and limit of quantification (S/N=10) of the target components ranged from 0.10-1.00ng and from 0.30-3.00ng, respectively. The coefficients of linear regression ranged from 0.9993-1.0000, all interday and intraday precision values were <3.64%, and the average recovery ranged from 99.00-102.97% for Astragali Radix and 97.73-102.57% for HGOT. This method exhibited good selectivity, sensitivity, and reproducibility and can be used directly without any pretreatment steps. Our method will therefore be useful as a quality control measure for Astragali Radix.

Tailoring and recycling of deep eutectic solvents as sustainable and efficient extraction media

The present study demonstrates that deep eutectic solvents (DESs) with the highest extractability can be designed by combining effective DES components from screening diverse DESs. The extraction of polar ginseng saponins from white ginseng was used as a way to demonstrate the tuneability as well as recyclability of DESs. A newly designed ternary DES (GPS-5) composed of glycerol, l-proline, and sucrose at 9:4:1 was used as a sustainable and efficient extraction medium. Based on the anti-tumor activity on HCT-116 cancer cells, it was confirmed that GPS-5 was merely an extraction solvent with no influence of the bioactivity of the ginsenosides extracted. Excellent recovery of the extracted saponins was easily achieved through solid-phase extraction (SPE). Recycling of the DES was accomplished by simple freeze-drying of the washed solutions from the SPE. The extraction efficiencies of the DESs recycled once, twice, and thrice were 92%, 85%, and 83% of that of the freshly synthesized solvent.

Recent methodology in ginseng analysis

As much as the popularity of ginseng in herbal prescriptions or remedies, ginseng has become the focus of research in many scientific fields. Analytical methodologies for ginseng, referred to as ginseng analysis hereafter, have been developed for bioactive component discovery, phytochemical profiling, quality control, and pharmacokinetic studies. This review summarizes the most recent advances in ginseng analysis in the past half-decade including emerging techniques and analytical trends. Ginseng analysis includes all of the leading analytical tools and serves as a representative model for the analytical research of herbal medicines.

Simultaneous analysis method for polar and non-polar ginsenosides in red ginseng by reversed-phase HPLC-PAD

The paper describes the development of a simultaneous determination method for polar and non-polar ginsenosides in red ginseng with a reversed-phase high-performance liquid chromatography-pulsed amperometric detection method. This method could be applied directly without any pretreatment steps and enabled the performance of highly sensitive analysis within 1h. The detection (S/N=3) and quantification (S/N=10) limits for the ginsenosides ranged 0.02-0.10 ng and 0.1-0.3 ng, respectively. The linear regression coefficients ranged 0.9975-0.9998. Intra- and inter-day precisions were <9.91%. The mean recoveries ranged 98.08-103.06%. The total amount of ginsenosides in the hairy root of red ginseng was higher than that in the main root.

Panax ginseng C.A. Meyer modulates the levels of MMP3 in S12 murine articular cartilage cell line

AIM OF THE STUDY

The destruction of cartilage in patients with osteoarthritis occurs due to an imbalance between matrix synthesis and degradation. Cartilage degradation is induced by the activation of matrix metalloproteinases (MMPs). Therefore, this study was conducted to evaluate the cartilage protective effect of Panax ginseng C.A. Meyer (PG).

MATERIALS AND METHODS

S12 cells were treated with various concentrations of extract of PG and gensenosides Rd and Rb(3) for 3h, after which 10 ng/ml interleukin-1beta (IL-1beta) was added to the culture media. The levels of MMP3 in the conditioned media were then evaluated using an enzyme-linked immunosorbent assay (ELISA). In addition, reverse transcriptase-polymerase chain reaction (RT-PCR) was used to evaluate the mRNA expression of Type II Collagen and Pro-collagenase. Furthermore, Western blot analysis was performed to identify the roles that PG played in the ERK and p38 signaling pathways.

RESULTS

The MMP3 secretion levels of S12 cells were significantly lowered in response to treatment with PG and gensenosides Rd and Rb(3) at a concentration of 100 microg/ml when compared to cells that were treated with IL-1beta. In addition, PG induced the mRNA expression of Type II Collagen dose dependently. Furthermore, phosphorylated p38 and ERK were detected in S12 articular cartilage cell line that was treated with IL-1beta. PG decreased the phosphorylation of p38, but PG did not exert any effect on phospho-ERK.

CONCLUSIONS

These findings indicate that PG and gensenosides Rd and Rb(3) suppress MMP3 secretion and that gensenosides Rd and Rb(3) are the major elements involved in the suppression of MMP3 by PG. Furthermore, the suppression of MMP3 by PG occurs via the inhibition of phospho-p38 activation. Therefore, PG may exert a protective effect against the cartilage degradation of OA.

Detection of albiflorin and paeoniflorin in Paeoniae radix by reversed-phase high-performance liquid chromatography with pulsed amperometric detection

We have developed a reversed-phase high-performance liquid chromatography-pulsed amperometric detection (RP-HPLC-PAD) method for the detection of albiflorin and paeoniflorin in Paeoniae Radix and Wu-ji-san. Albiflorin and paeoniflorin were completely separated using 10% acetonitrile in 5mM sodium phosphate buffer (pH 3.0) as an eluent and detected by PAD under alkaline conditions after using a post-column delivery system. The limit of detection (S/N=3) and the limit of quantification (S/N=10) were 0.10 and 0.35 ng for albiflorin, and 0.20 and 0.50 ng for paeoniflorin, respectively. The coefficients of linear regression were 0.9995 and 0.9999 for concentrations between 0.035 and 100 microg/mL. The intra- and inter-day precision (RSDs) was less than 3.56% in Paeoniae Radix and Wu-ji-san. The average recoveries from Paeoniae Radix and Wu-ji-san were 99.01-100.94% and 99.46-100.64%. This method shows higher selectivity than HPLC-UV method for analyzing albiflorin and paeoniflorin in Chinese medicinal preparation.

Sensitive high-performance liquid chromatography method of non-polar ginsenosides by alkaline-enhanced pulsed amperometric detection

We determined the minute amount of non-polar ginsenosides in red ginseng with a reversed-phase high-performance liquid chromatography-pulsed amperometric detection (RP-HPLC-PAD) method. Non-polar ginsenosides efficiently extracted by ethyl acetate were well separated in 40min using a water-acetonitrile gradient eluent and detected by PAD under NaOH alkaline conditions. The ginsenoside detection limits (S/N=3) were 0.03-0.10ng. The coefficients of linear regression were 0.9972-0.9990. Intra- and inter-day precision (RSDs) was less than 8.34% and average recovery was 98.06-102.73%. The total amount of non-polar ginsenosides in hairy root of red ginseng was slightly higher than in the main root.

Rapid method for simultaneous determination of flavonoid, saponins and polyacetylenes in folium ginseng and radix ginseng by pressurized liquid extraction and high-performance liquid chromatography coupled with diode array detection and mass spectrometry

A rapid pressurized liquid extraction (PLE) and high-performance liquid chromatography coupled with diode array detection and mass spectrometry (HPLC-DAD-MS) method for the simultaneous determination of one flavonoid (panasenoside), nine saponins (ginsenoside Rg1, Re, Rf, Rg2, Rb1, Rc, Rb2, Rb3 and Rd) and two polyacetylenes (panaxydol and panaxynol) in folium ginseng and radix ginseng was developed. A Prevail C(18) rocket column (33 mm x 7 mm, 3.0 microm) and gradient elution were used during the analysis. Flavonoid was quantified at 355 nm, and saponins and polyacetylenes were determined at 203 nm. The chromatographic peaks of 12 investigated compounds in samples were unambiguously identified by compared their UV spectra and/or MS data with the related reference compounds. All calibration curves showed good linearity (r>0.999) within the test ranges. The intra- and inter-day variations for 12 analytes were less than 1.17% and 2.17%, respectively. The developed method was successfully applied to determine the investigated compounds in 10 samples of radix ginseng and folium ginseng, respectively. The result showed that PLE combined with rocket column HPLC analysis could provide a rapid method for analysis of compounds in traditional Chinese medicines (TCMs), which is helpful to comprehensive evaluation of quality of radix ginseng and folium ginseng.