| 1. Structure, properties, extraction and analysis methods, as well as the application status of TP, TPS, theanine and catechin monomers were summarized. Besides, all the advantages and disadvantages of the mentioned extraction and analysis methods were compared respectively.2. Rizhao green tea was used as material in this study. Both orthogonal experiment and single-factor experiment were used to study the effect of W/V rate, extraction time and temperature on the extraction result. The optimized extraction programs are as follows:under the condition of stirring, extracted by20times distilled water at70℃, and this extraction was devided into2times and each for45min.Under this condition, the extraction rate of TP,TPS and Theanine are13.83%,2.57%and0.29%.3. Extraction technology of tea polyphenols, tea polysaccharide and theanine from the above water extraction liquid was confirmed by researches on selections of extractants and properties of ion-exchange resin. Parallel experiment was used to study the effect of ethylacetate extraction times on the actual yield rate of TP, and the effect of PH on the adsorption and desorption of732cation exchange resin. The optimized separation programs are as follows:the extract solution is concentrated to a solid content of5%, extracted two times with the same volume ethylacetate, phased with ethylacetate, obtained TP by drying after the reduced pressure distillation, and recovered ethylacetate, the tea polysaccharide yield rate is19.78; then adjusting the aqueous phase, PH is3, and exchanging resins with732cationic which is processed, the column elution liquid is tea polysaccharide, the rate is1.76%; finally eluted the column with the phosphate buffer which PH is8.0, obtained the tea polysaccharide gathering liquid, the rate is0.19%.4. Supported cellular geltyperesin was formed by blending, melting and solubling, using inorganic as pore former and thermoplastic resin as crosslinking agent. Then thorough the orthogonal experiment and the single factor parallel test, it inspected the effect of the heating time, heating temperature and the mass ratio of thermoplastic resin and the porogen on the new carrier synthesis, and as the indexes of the recovery rate and salt-leaching rate, got the best optimized programs: materials rate of PE:geltyperesin:NaCL:NH4HCO3(g)=3:2:39:5. moltened by180℃and45min. Under this condition, the rate of desalination is83.2%.5. Using the supported cellular geltyperesin as packing, it isolated and purified the catechin EGCG monomer, through the dynamic adsorption and elution experiments, and respectively inspected the effect of the chromatography column diameter, the sample volume, the eluent concentration and flow velocity on EGCG. Ultimately the optimized separation programs are as follows:the chromatography column diameter2.5cm, the sample volume1.5g,70%ethanol solution as eluent, flow velocity0.8-1.0ml/min, collecting fractions, that EGCG was tested to the separation degree is93.38%, elution rate is84.51%, the yield rate is78.92%, the purity is more than96.00%.6. Separately using the quality of LH-20geltyperesin and supported cellular geltyperesin as packing, it did the dynamic elution experiments on the catechin EGCG monomer. Under the condition of the sample volume1.5g,70%ethanol solution as eluent, flow velocity0.8-1.0ml/min, the comparison test proved:using supported cellular geltyperesin as packing, the extraction and purity of EGCG monomer are severally5%and1%higher than the test using a pure LH-20geltyperesin of the same quality as packing, in addition the elution time and eluent dosage are significantly reduced, and flow velocity is easily controled, that improve work efficiency and save the economic costs. |
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