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- Author or Editor: J. Liang x
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Summary
An HPLC-DAD-ESI-MSn method has been developed for simultaneous quantification of eight major compounds in eight Saussurea species which have long been used as the traditional Tibetan medicines. The method was validated for sensitivity, precision, and accuracy. LODs were from 0.11 to 5.01 μg mL−1, overall intra-day and inter-day variation was less than 2.70%, and overall recovery was over 98.0%. The correlation coefficients (r 2) of the calibration plots were >0.991. This newly established method was successfully used to reveal difference among the chemical profiles and analytes contents of eight Saussurea species collected in Tibet. In addition, by comparison of UV and mass spectra with those of authentic compounds, a total of fifteen peaks were identified. It can be concluded that this is an effective method for quantification and evaluation of the flavonoids and coumarins in the eight species of the genus Saussurea. It can be used as an efficient reference method for development and use of the eight traditional Tibetan medicines by comparing their different characteristics.
A high-speed counter-current chromatography (HSCCC) method was established for the isolation and purification of isochlorogenic acid A from Lonicera japonica Thunb. The two-phase solvent system was composed of n-hexane:ethyl acetate: isopropanol:water (2:3:2:5, v/v/v/v). From 150 mg of the ethyl acetate fraction of L. japonica Thunb, 19.65 mg of isochlorogenic acid A was obtained in a one-step HSCCC separation, with a purity of 99.1%, as determined by high-performance liquid chromatography (HPLC). The structure was further identified by ultraviolet (UV), mass spectrometry (MS) and nuclear magnetic resonance (NMR).
Citri Grandis Exocarpium (CGE) is a traditional Chinese medicine with a variety of biological activities. For efficient quality control of CGE, a simple, rapid, and accurate high-performance liquid chromatographic (HPLC) method was developed for simultaneous determination of four main compounds (naringin, rhoifolin, meranzin hydrate, and isoimperatorin) in this herb. These four compounds were separated on a C18 column by gradient elution with methanol and water. The flow rate was 1.0 mL·min−1, and the detection wavelength was 324 nm. The recoveries of the method ranged from 96.32% to 103.71%, and good linear relationships (r 2 > 0.9998) over relative wide concentration ranges were obtained. Then this validated method was successfully applied to the analysis of nine batches of CGE samples.
Shuganjieyu (SGJY) capsule is a classical formula widely used in Chinese clinical application. In this paper, an ultra-performance liquid chromatography coupled with electrospray ionization and ion trap mass spectrometry has been established to separate and identify the chemical constituents of SGJY and the multiple constituents of SGJY in rats. The chromatographic separation was performed on a C18 RRHD column (150 × 2.1 mm, 1.8 μm), while 0.1% formic acid–water and 0.1% formic acid–acetonitrile was used as mobile phase. Mass spectral data were acquired in both positive and negative modes. On the basis of the characteristic retention time (R t) and mass spectral data with those of reference standards and relevant references, 73 constituents from the SGJY and 15 ingredients including 10 original constituents and 5 metabolites from the rat plasma after oral administration of SGJY were identified or tentatively characterized. This study provided helpful chemical information for further pharmacology and active mechanism research on SGJY.
