Quality Control of Traditional Chinese Medicine: Analysis of marker components in Banlangen and aflatoxin in Zizyphus fructus by LC/MS

Autor: Bing-Chung Liau, 廖炳創
Rok vydání: 2007
Druh dokumentu: 學位論文 ; thesis
Popis: 95
This dissertation consists of three parts, which belong to the quality control of traditional Chinese medicines (TCMs). In this study, a liquid chromatography mass spectrometry (LC/MS) or liquid chromatography tandem mass spectrometry (LC/MS/MS) was developed to analyze TCMs, including Isatis indigotica (Banlangen & Daqingye) and Zizyphi jujube (Zizyphus fructus). The abstracts are as follows: In first part, a rapid, selective, and sensitive LC/APCI-MS method is developed in this study for detecting and analyzing tryptanthrin, indigo, and indirubin in Daqingye and Banlangen, which are, respectively, the leaves and roots of Isatis indigotica and Strobilanthes cusia in traditional Chinese medicine. The detection of the three active components is linear in concentrations ranging from 100 to 1500 ng/mL, the squared correlation coefficient is higher than 0.996, the precision as measured by the relative standard deviation is no larger than 9.5%, and the recovery is greater than 86.6%. The analysis of the 21 Banlangen samples led to considerably different conclusions on the contents of tryptanthrin, indigo, and indirubin in fresh leaves versus those in dried leaves. These results should shed some light on future plant selection and breeding. Compared with the traditional TLC and HPLC-UV methods, the new LC/APCI-MS approach has proven to be an optimal tool for detecting and analyzing the three marker compounds in the Chinese herbal medicines of Daqingye and Banlangen. In second part, the analytical method in this part was the same as part 1, which was also used to analyze three marker componets in Banlangen by LC/APCI-MS. However, in this part, the content difference in nanolized or un-nanolized Banlangen was compared. The results indicates that the contents of marker components in nanolized Banlangen (300nm) > in microlized Banlangen (5 µm) > in Banlangen ground by lab (~0.5 mm). The content of tryptanthrin was increased as 2.4 folds, indigo 3.4 folds, and indirubin 3.3 folds comparing with/without nanolization. This phenomenon may be caused by the increasement of total surface area in nanolized Banlangen, then, increased the extraction efficiency by MeOH For the detection of concentrated extracts with herb, the method was failed to analyze the marker components in Banlangen due to the influence of complicate matrix. The complicate matrix was probably produced by formalization agent, and it could be moved with pretreament techniques, such as solid phase extraction (SPE). In third part, an integrated method supercritical fluid extraction (SFE) with LC/APCI-MS/MS was developed and successfully applied to quantify aflatoxins (AFs) in Zizyphi Fructus (fruits of Zizyphus jujube), a traditional Chinese medicine. To minimize the potential interferences caused by the complex matrix in Zizyphi Fructus, a SFE pretreatment was performed. In addition, electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) spectra were also compared. The results showed that the calibration curves of AFB1, AFB2, AFG1, and AFG2 were all linear over the range of concentration from 1 to 50 ng/g, the squared correlation coefficients (r2) were over 0.995, and the detection limits of method were between 0.17 and 0.32 ng/g. It showed high recovery and good precision in quantitating AFs in Zizyphi Fructus without further clean-up. Further, the fragmentation pathways of protonated AFs in APCI MS/MS were clearly proposed which could predict the existence of AFB or AFG series. To test the empirical validity of the proposed methodology in this paper, eight random samples of Zizyphi Fructus collected from supermarkets and traditional Chinese medicine stores in different geographical areas of Taiwan were analyzed. The results indicated that low levels of AFs were detected in only one of them.
Databáze: Networked Digital Library of Theses & Dissertations
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