Resolution and identification of the acidic fraction of a petroleum ether extract ofRadix Rehmanniae Preparata by an evolving chemometric approach

Abstract

Key WordsGas ch romatog rag hy -mass spectrometry Chemometrics Su bwindow factor analysis Rehmannia glutinosa Libosch Scrophulariaceae Summary An evolving approach is described for analyzing the acidic components of a petroleum ether extract of Radix Rehmanniae Preparata. The latter was extracted, separated and derivatized. The subsequent separation of the individual components was characterized by GC-MS. The Iwo-way data were resolved into a pure chromatogram and a mass spectrum of each chemical component. The reliability and accuracy of the qualitative results were greatly improved and the degree of the chromatographic separation could be enhanced to a certain extent. This enabled the analysis of complicated practical systems by hyphenated instruments and these advanced methods.

Quality control of herbal medicines

“…EI is particularly useful for routine analysis and provides reproducible mass spectra with structural information which allows library searching. GC-MS was the first successful online combination of chromatography with mass spectrometry, and is widely used in the analysis of essential oil in herbal medicines [111][112][113][114][115][116][117][118][119][120][121][122][123][124][125].…”

“…With the GC-MS, people could produce not only a chromatographic fingerprint of the essential oil of the herbal medicine but also the information related to its most qualitative and relative quantitative composition [116][117][118][119][120]126,127]. Used in the analysis of the herbal medicines, there are at least two significant advantages for GC-MS, that is: (1) with the capillary column, GC-MS has in general very good separation ability, which can produce a chemical fingerprint of high quality; (2) with the coupled mass spectroscopy and the corresponding mass spectral database, the qualitative and relatively quantitative composition information of the herb investigated could be provided by GC-MS, which will be extremely useful for the further research for elucidating the relationship between chemical constituents in herbal medicine and its pharmacology in further research.…”

Alternative moving window factor analysis (AMWFA) for resolution of embedded peaks in complex GC-MS dataset of metabonomics/metabolomics study

“…These methods have shown their potential in many fields. 1,[11][12][13][14] However, a special case called embedded peaks is often existent in chromatography, especially in the analysis of metabolites and traditional Chinese medicines. For this case, the assumption of ''first-in-first-out'' will not be available and the above resolution techniques seem to be helpless.…”

Recent advances in the compound-oriented and pattern-oriented approaches to the quality control of herbal medicines

“…In another study, 69 components of Radix Rehmanniae Preparata ( Shudihuang ) were separated, of which 59 were identified using standard spectra in the database of the National Institute of Standards and Technology (NIST). The 26 identified methyl esters accounted for about 94.29% of the total number of components [ 53 ]. Most of the iterative methods including (orthogonal projection approach) OPA and (iterative orthogonal projection resolution) IOP were applied to determine the chemical composition of herbal medicines [ 45 , 46 ].…”

“…PCA, orthogonal projection technique (OP), 2D-IR worked well on data discrimination analysis of fingerprints [ 94 - 97 ]. Data deconvolution methods helped obtain chromatographic and spectral profiles of individual pure components [ 47 - 53 ]. Furthermore, chemical fingerprint databases of herbal medicines were developed according to chemometric methods [ 98 , 99 ].…”