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

Abstract

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.

Heterologous expression of Bacillus subtilis SL-44 glycosyltransferase catalyzed synthesis of ginsenoside Rh2

“…Bacillus subtilis strain SL-44 (laboratory culture), expression vector pET-28a, cloning vector pUCmt, E. coli BL21 (DE3), and DH5a were provided by Bioengineering (Shanghai) Co [20]. The specific protein sequences of the primers used in this study are shown in Table 1 [21]. Induced recombinant E. coli cells were collected by centrifugation at 8000 rpm for 5 min at 4 mg/L.…”

The Importance of Reference Materials and Method Validation for Advancing Research on the Health Effects of Dietary Supplements and Other Natural Products

“…While the primary focus of the NIH-ODS/NIST collaboration has been to provide matrix SRMs for the dietary supplement community, several calibration solution SRMs were also developed by NIST between 2011 and 2016 for catechins, hypericin, organic acids, and isoflavones. Currently, the only botanical dietary supplement ingredient calibration solution available from NIST is SRM 3389 Ginsenosides Calibration Solution ( 47 ). Another calibration solution CRM for ginsenosides is also available from the National Research Council of Canada (the NMI for Canada) as well as three pure reference standards for constituents associated with plants used as ingredients in dietary supplements 13 (see Table 4 ).…”

Isolation and Identification of Non-Conjugated Linoleic Acid from Processed Panax ginseng Using LC-MS/MS and 1H-NMR

“…Ginsenoside profiles and linoleic acid contents were analyzed for the ginseng samples at each cycle of the steaming and drying process with a selected ion monitoring (SIM) method, as listed in Table 1. Formic acid adduct ion [M-H+HCOOH] − was monitored because much higher signal abundance was observed than with deprotonated ion [M-H] − [21]. The raw data were processed using QuanLynx TM in MassLynx TM ver.…”