| Eucommia ulmiodes, a dioecious tree, is a native plant species of China. It's bark is a traditional Chinese medicine. Modern scientific research has reported that the leaf and flower of Eucommia ulmoides also has some pharmacological effects similar to the bark and some processed products have developed. Some studies have previously reported the processing technology of the Eucommia Staminate Flower Tea. However, information concerning the change of bioactive components during the precessing is rather scarce. In this work, the experiments were systematically carried out on the change of bioactive components during the processing of the Eucommia Staminate Flower Tea followed review of the chemcial components and healthy functions of the Eucommia Staminate Flower Tea. The results were as follows:(1) A reverse phase C18 HPLC method has been developed for the quantitative analysis of chlorogenic acid in Eucommia ulmiodes extracts. Separation was performed on a Kromasil-C18 column (250×4.6 mm i.d., 5μm) at room temperature. The elution solvent was acetonitrile / 0.4% phosphoric acid (8:92, v/v) applied at a flow rate of 1ml/min. The detection wavelength was set at 327 nm. Chromatography gave rise to a distinct UV-absorbing peak of chlorogenic acid with good basebine separation from other compounds. A excellent correlation was obtained with a linear analytical response from 0.05 to 0.55μg of chlorogenic acid. The recovery of chlorogenic acid with this HPLC method was 98.80%. The sample solution was stable within 16 hours. The method is available for quantitation and control of chlorogenic acid due to its accuracy, time-saving and simplicity( convenience) for routine analysis.(2) The optimum extraction conditions of chlorogenic acid from male flowers tea of Eucommia ulmoides Olive were obtained using orthogonal test which was as follows: methanol concentration 50%, material to solvent 1: 30, extraction temperature 60℃, refluxing extraction time 30 minutes and extraction for twice.(3) The content of flavonoids was measured using a colorimetric method. A excellent correlation was obtained with a linear analytical response from 0.02 to 0.1mg of flavonoids. The sample solution was stable within 3 hours. The red colour of the flavonoid-aluminium complex produced in the reaction was found to be unchanged within 30 minutes. The recovery of flavonoids with this method was 102.2%. The colorimetric method showed convenience and good repeatability and can be adopted as a routine method for quantitation and control of flavonoids.(4) The optimum extraction conditions of flavonoids from male flowers of Eucommia ulmoides Olive were studied using single factor experiments and orthogonal test. The results showed that optimum extraction condition is as follows: ethanol concentration 60% , extraction temperature 90℃, material to solvent 1: 40, extraction time 2 hours, and extraction for twice. The order of main factors influencing the extraction by importance was as follows: enthanol concentration, extraction temperature, material to solvent and extraction time. The results also showed the effects of ethanol concentration and extraction temperature on extraction are statisticallly highly significant while the effects of material to solvent and extraction time are significant.(5) The content of chlorogenic acid in the four stages (fresh flower, fixing, drying and second drying) during the processing of the Eucommia Staminate Flower Tea are 0.501%,0.391%,0.363%,0.34%. The content of total flavonoid are: 1.77% ( the fresh flower of the Eucommia Staminate Flower ), 1.61% ( after fixing ), 1.97% ( after drying ), 2.07% ( after second drying as the finished product of the Eucommia Staminate Flower Tea. The chlorogenic acid content of the Tea showed a remarkably reduced trend during processing.The important decrease with 22% loss ratio of chlorogenic acid were measured after fixing while the content of chlorogenic acid were slightly reduced during fixing and second drying. The content of total flavonoids was dramatically increased after fixing, drying and second drying. Compared to fresh flower, the content of total flavonoid was increased by 16.78% after second drying.
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