| Chrysanthemum(Chrysanthemum morifolium Ramat)is a traditional Chinese medicine, but its medical effect differs depended on its species. In order to control its quality and to discriminate the species of Chrysanthemum, it was required to determine the active ingredients in different Chrysanthemum by high-performance capillary electrophoresis (CE) combined with electrochemical detection (ED) and to develop the fingerprint by high performance liquid chromatography (HPLC) methods. Additionally,the antioxidant capacity of different species of Chrysanthemum was studied.Firstly,carbohydrates are the substances providing energy for respiration. And they were so steady and characteristic that they were used as the marker for quality control. A high-performance capillary electrophoresis (CE) combined with electrochemical detection (ED) method has been employed for the determination of alditol and six carbohydrates including mannitol, sucrose, galactose, glucose, rhamnose, mannitose, and fructose in Chrysanthemum. Operated in a wall-jet configuration, a 200μm diameter copper-disk electrode was used as the working electrode positioned opposite the outlet of capillary. Good linear relationship was established between the peak area and the concentration of seven analytes. Simultaneously, these 11 batches of Chrysanthemum collected from different regions in China were applied to establish the fingerprints. The data from the common peaks were processed with two kinds of mathematical methods including correlation coefficient and the included angle cosine.Secondly,some important active ingredients in Chrysanthemum were quantitative studied. The method CE-ED method developed in Chapter Two has also been used for the determination of five active ingredients-chrysin, baicalin, chlorogenic acid, luteolin and quercetin- in Chrysanthemum. The working electrode was a 300μm diameter carbon disc electrode positioned opposite the outlet of capillary. Under the optimum conditions, the analytes were baseline separated within 20min in a 70cm length capillary at the separation voltage of 16kV in a 50mmol/L borate buffer (pH=9.2). Notably, excellent linearity was obtained over three orders of magnitude for all five analytes with detection limits (S/N=3) ranged from 10-4 g/mL to 10-6g/ mL. The relative standard deviations of the migration time and peak area of five analytes ranged from 1.5 to 3.5%, and from 1.9 to 3.6%, respectively. The recoveries of five constituents were between 97.3 and 104.1%, and the detection limit were between 1.1×10-7 g/mL and 3.3×10-7g/mL. This method was successfully used in the analysis of Chrysanthemum with a simple extraction procedure, and the assay results were satisfactory.A high performance liquid chromatography (HPLC) method possess the virtues such as accuracy, stability and reproducibility, so it was developed to establish the fingerprint of Chrysanthemum. The HPLC conditions were as follows: Nov-pak C18 (250×3.9mm I.D, 5μm) as separation column, 0.1% phosphoric acid aqueous solution - methanol as mobile phase with gradient elution, flow rate at 0.6mL/min, 254nm as the optimum detection wavelength. The fingerprints of Chrysanthemum were established with the included angle cosine and correlation coefficient methods to calculate the similarity of Chrysanthemum samples. According to the result of correlation coefficient, the MATLAB procedure was applied for the cluster analysis, and the result is consistent with the species of the actual samples. It provides the criterion for quality control and discrimination of Chrysanthemum.High-performance capillary electrophoresis (CE) with electrochemical detection (ED) was employed to study hydroxyl radical in the CuSO4-Vitamin C reaction (pH=7.4). Operated in a wall-jet configuration, a 300μm diameter carbon-disc electrode was used as the working electrode. Excellent linearity was obtained in the concentration ranged from 1.5×10-4 mol/L to 6.0×10-6mol/L for the productant. The detection limit (S/N=3) was 1.5×10-6mol/L. This method was successfully applied for studying hydroxyl radical scavenging activities of Chrysanthemum.
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