The Application Of Chemometric Methods In The Research Of Economic Plants

Thousands of components in plants make it very complicated to research. And the special consuming ways like tobacco smoking and tea steeping make the researchment of plants even more difficult. With the help of chemometric methods and modern instrument analytical technology such as chromatography, the analyse of economic plants is becoming effectively.Based on chromatography analysis, the application of chemometric methods in the research of economic plants is discussed. Two parts are involved in this paper. In the first part, chemometric methods are used to resolve GC-MS data of total particulate matter in mainstream smoke of tobacco after silylating. Principal Component Analysis (PCA) is applied to estimate the number of chemical compositions in the chromatographic peaks. Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) method is employed to resolve the overlapped chromatograms. The initial estimate for MCR-ALS is collected by picking the most dissimilar chromatographic profiles. And the resolved chromatographic profiles are scaled based on the total ion chromatogram. The resolution method is applied to GC-MS data of a selected total particulate matter in mainstream smoke of tobacco sample. 16.8% of the chromatographic peaks are overlapped chromatograms containing two or three components. After resolution, pure chromatographic profiles and mass spectra are obtained. Satisfactory results illustrate that the resolution methods are powerful approaches for the determination of the number of chemical compositions contained in the investigated chromatographic peaks and the resolution of overlapped chromatograms.In the second part, the release kinetics of green tea is researched by the help of HPLC. A gradient HPLC procedure is developed to separate Xihu Longjing infusion. The stability of catechin components is researched. The contents of those components have no obvious change in lasting five hours. The dissolving process of several tea compositions from the tea leaves to water are...