| To build chemical characteristic fingerprint of traditional Chinese medicine (TCM) has been becoming the most efficient measure for quality control of TCM or natural medicines, and it would certainly become the powerful means for standardizing of producing process for TCM. With the rapid development of hyphenated instruments and related chemometric methods, it is possible to provide powerful tools and extensive prospect for the building and evaluating of TCM fingerprint. In this paper, the TCM systems are taken as the research target. With the help of GC, GC-MS,HPLC-DAD separation and detection combining related chemometric methods, the chromatographic fingerprints of Notoptergium incium ting ex H.T.Chang and Artemisia capillaris Thunb have been built. Then, they were evaluated by the criteria of common peak rate, variance rate and similarity of fingerprint. At last, the research methods for TCM fingerprints are applied to the quality control of tobacco flavor. In conclusion, the thesis is mainly referred to several aspects:1.Resolution of overlapping peaks: to obtain the pure chromatogram and pure spectrum of the overlapping peaks, overlap index is taken as the criteria for the selection of iterative orthogonal projection approach (OPA) and noniterative evolving window orthogonal projection (EWOP). To those components with lower intensity and signal to noise, the raw data is pretreatedby roughness penalty smoothing method. With the data denoised, heteroscedastic noise and signal-to-noise ratio were decreased apparently without changing the basic structure of the data and losing qualitative information. However, qualitative and quantitative accuracy was improved by above process.2.Optimization of extraction and separation conditions by information theory: the idea of information theory is used to the optimization of chromatographic separation and sample extraction condition for the first time. By calculating information content of the chromatogram, the separation content is evaluated in the whole, but not locally from resolution separation degree of several components. Furthermore, it can embody the information of component number and content in the whole.3. Evaluation of the chromatographic fingerprint: orthogonal projection approach is used for the extraction of common peaks, which improved the capability of identification of common peaks and decreased the difficulty of identification of common peaks because of retention time drift, lower matching degree from mass library and overlapping of chromatographic peaks. The volatile constituents of Artemisia capillaris Thunb from four different sources were evaluated in the whole and individual by the similarity of fingerprints and modified common peak rate, variance rate.4. Quality control of tobacco flavor: in this paper, the research methods for TCM fingerprint are applied to the quality control of tobacco flavor. Theflavor constituents of about 20 tobacco flavors were extracted by solvent extraction, hydro-distillation, simultaneous distillation-solvent extraction aind solid phase micro-extraction. Then, the characteristic fingerprints were obtained through GC-MS. The pattern recognition of the tobacco flavors were built by principle component analysis and clustering analysis. The automatic estimation of tobacco flavor' quality was achieved by the software for quality control of tobacco flavor. |
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