| Two novel types of sample pretreatment techniques (ultrasound - and microwave - assisted extraction approaches) have been used for the extraction of polyphenolic compounds, like chlorogenic acid, caffeic acid, and so on, from Eucommia ulmodies Oliv., a precious Traditional Chinese Medicine existed in the west of Hunan province, in this work. The influence of various extraction parameters in each technique on the extraction efficiencies of the tested compounds has been investigated. Additionally, synthesis and chromatographic behavior of the molecularly imprinted polymers have also been studied. Separation and purification of chlorogenic acid from Eucommia olmodies Oliv. leaves extracts by solid phase extraction of caffeic acid imprinted polymer stationary phase monolith prepared by an in-situ polymerization technique was investigated. This work was financially supported from China NSF, China MST and Hunan Provincial Department of Science & Technology.1. Based on the accelerated mass transfer of the endocyte to the extractionsolvent after the plant cells were crashed by ultrasonic wave, an ultrasonic method for the extraction of chlorogenic acid from Eucommia ulmodies Oliv. using simple cleaning bath was designed. The influence of four extraction variables on extraction efficiency of chlorogenic acid was investigated. Results showed that ultrasonically assisted extraction technique could produce a higher extraction efficiency and consumed less solvent compared with the extraction without ultrasound. A lower temperature in the ultrasonic system increased the stability of the extracted compounds. The application of sonication method was shown to be highly efficient in the extraction of chlorogenic acid from Eucommia ulmodies Oliv. compared with classical methods.2. A new focused microwave-assisted solvent extraction method using water assolvent has been developed for leaching geniposidic and chlorogenic acids from Eucommia ulmodies Oliv.. The extraction conditions were optimized using a two indexes orthogonal experimental design and graphical analysis, by varying irradiation time, solvent volume, solvent composition and microwave power. Microwave-assisted extraction approach greatly shortened the extraction time and increased the extraction efficiency of the compounds.The R.S.D. of the extraction process for both geniposidic and chlorogenic acid were satisfactory.3. An open microwave-assisted extraction system was used to extract polyphenolic compounds, like gallic acid, protocatechuic acid, chlorogenic acid and caffeic acid from Eucommia ulmodies Oliv.. The effect of extraction variables, especially, the solvent composition and volume on the recoveries of these polyphenolic compounds was investigated. Methanol, as extractant, produced a higher recovery than pure water. For straight chain alcohol solvents, the smaller the carbon number, the higher the recoveries of these polyphenolic acids. The optimal ratio of methanol: water: glacial acetic acid in the solvent mixture used in microwave-assisted extraction was 2:8:0.3 (v/v) and this solvent could be directly used as the mobile phase in HPLC separation without additional intermittent treatment as reported in literature. The repeatability of extraction method and chromatographic analysis was satisfactory for the analysis of these polyphenolic compounds.4. A non-covalent imprinting approach was applied to synthesize protocatechuicacid (3,4-dihydroxybenzoic acid) imprinted polymers (MIPs) in the polar tetrahydrofuran by using protocatechuic acid as the template, methacrylic acid (MAA) as functional monomer, ethylene glycol dimethacrylate (EDMA) as cross-linker. By equilibrium adsorption experiments and high performance liquid chromatography (HPLC), the rebinding properties of the MIPs to protocatechuic acid (template) and its analogues were evaluated. The Scatchard analysis method was used for the detection of the types and energy distribution of binding sites in the polymer. The MIP exhibited high adsorption capability...
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