Analytic Determination Of The Active Ingredients In Tea And Traditional Chinese Medicine Curcuma Longa L. By High Performance Liquid Chromatography With Fluorescence And Ultraviolet Detection

Fluorescent properties of different kinds of catechins and curcumins were studied in this thesis. Influence of experimental conditions on fluoresence spectra was investigated. A new method for the qualitative and quantitative analysis of active ingredients in tea and Curcuma longa L. by HPLC with fluorescence detection was developed in this thesis.Two parts are included in the thesis:1. An analytical method, based on HPLC with fluorescence detector, has been developed and validated for the simultaneous determination of catechin, epicatechin, gallocatechin, epigallocatechin, catechin gallate, epicatechin gallate, gallocatechin gallate, epigallocatechin gallate in tea. The catechins were separated on the Zorbax SB-C18 column(5 μm, 150 mm×4.6 mm) by gradient elution using mixed solutions of methanol and 0.1% phosphoric acid in different proportions. The separation was carried out within 20 minutes with the flow rate of 1.0 m L·min-1 and the column temperature of 35 oC. The method has wider linear range and higher sensitivity, the RSD of stability and precision value were between 0.63% and 0.98%, the overall mean recovery ranged from 87.7% to 106.1%. The method is used for the qualitative and quantitative analysis of eight kinds of catechins in tea, the results are accurate and reliable.2. An analytical method, based on HPLC with fluorescence detector, has been developed and validated for the simultaneous determination of curcumin, demethoxycurcumin, and bisdemethoxycurcumin in Curcuma longa L.. The method uses the Zorbax SB-C18 column(5 μm, 250 mm×4.6 mm) and acetonitrile-0.1% formic acid(50:50) mobile phase system to separate the three curcumins. The separation was carried out within 12 minutes by isocratic elution with flow rate 1.0m L·min-1, column temperature at 25 oC, and detection wavelength at λex/λem=432/524 nm. The method has wider linear range and higher sensitivity, the RSD of stability and precision value were between 0.48% and 0.92%, the overall mean recovery ranged from 98.7% to 103.7%. The method is used for the qualitative and quantitative analysis of three kinds of curcumins in Curcuma longa L., the results are accurate and reliable.