The Extraction And Isolation Of Active Ingredients Of Eucommia Leaf And Fruit And The Oxidation Stability Of Eucommia Seed Oil

In this dissertation, we took the leaves and samara of Eucommia that is endemic species in China as raw material, studying the extraction technology of chlorogenic acid and samara oil to optimize the extraction process. We used macro porous resin to achieve separation and purification of chlorogenic acid. The effects on oxidation stability of samara oil at different accelerated conditions were compared. The dissertation made research by the numbers on effective extraction of chlorogenic acid and samara oil. The primary coverage was as follows.Set up HPLC method which was for determining the content of chlorogenic acid. Chromatographic separation was carried out by a Kromasil-C18(5μm,4.6mm×250mm) reversed-phase column, the mobile phase is methanol-water-phosphoric acid (22:78:0.3, v/v/v). Chlorogenic acid was quantified by a UVD following RP-HPLC separation at the wavelength of328nm. The flow rate was1ml/min, the injection volume was10μL and the column temperature was maintained at25℃, retention time was35min.Take the method of ionic liquids-ultrasound-assisted extraction (ILUAE) to extract the chlorogenic acid from Eucommia leaves. The ionic liquids with different cations and anions were investigated in this work and0.5mol/L1-butyl-3-methylimidazolium bromide solution was selected as solvent. In addition, the technical parameters including soaking time, liquid-solid ratio, ultrasonic power and time were optimized. Soking time was2h. Base on the Single-factor experiments; a three-factor-three-level experiment design had been developed by Central Composite experiment design method. The optimized conditions were as follows: ultrasonic power200W, extraction time was45min, the ratio of liquid to solid was16:1. The actual yield of chlorogenic acid was0.71mg/g. Compared with the conventional solvent extraction, the proposed approach exhibited higher efficiency, which indicated the ILUAE was an efficient, rapid and simple sample preparation technique.The performance of seven macroporous resins for the enrichment and purification of chlorogenic acid from crude extract had been evaluated, including D101、HPD400A、 HPD722、HPD750、HPD850、HPD500and ADS-17. The optimum purification parameters were established:HPD750resin was screened out from seven kinds of macroporous resin; it was the optimum macroporous resin to purify chlorogenic acid. The best purification process conditions:adsorption temperature was25℃, saturated adsorption time was4hours, the concentration of crude extract was0.38mg/mL, chlorogenic acid adsorption capacity was3.56mg/g; degreasing agent was90%ethanol solution, desorption time was1.5h, desorption temperature was50℃, chlorogenic acid content of desorption solution was3.34mg/mL.Take the method of ultrasound-assisted sovent extraction to extract the samara oil from Eucommia samara. The n-hexane was selected as solvent. In addition, the technical parameters including soaking time, liquid-solid ratio, ultrasonic power, time and tempreture were optimized. Soking time was3h. Base on the Single-factor experiments. A three-factor-three-level experiment design has been developed by Central Composite experiment design method. The optimized conditions were as follows:ultrasonic power was200W, extraction time was40min, extraction tempreture was50℃, and the ratio of solid to liquid was20:1. The samara oil yeild was0.29g/g.According to the national standard method, peroxide value, anisidine value, acid value, conjugated diene value and MDA content of Eucommia samara oil under different conditions were measured and compared. The results showed that the degree of oxidation of the Eucommia samara oil stored at high temperatures, fried, microwave radiation was small and the Eucommia samara oil was stable relatively. While under UV irradiation conditions, severe oxidation was observed. And the oil was easy to rancidity. Therefore, it is very important to avoid Eucommia samara oil exposure to UV radiation in processing, storage, transportation and consumption. We should also try to avoid high-temperature conditions of storage, avoid prolonged frying or microwave radiation.