Study On Scale Preparation Of Highly Pure Chlorogenic Acid From The Crude Extracts Of Eucommia Ulmoides Leaves

Chlorogenic acid(CGA),as a kind of natural polyphenols and the effective ingredient of many chinese patent medicines,has received much attention because of its important biological activities,including lowering blood pressure,anti-microbial,antitumor,protecting liver and gallbladder.CGA has been widely applied in pharmaceutical industry,food industry and cosmetics industry.It has great significance to research the preparation of highly pure CGA for our national economy and social development.In this paper,a reliable,simple and stable technology route of purification and preparation of highly pure CGA from the crude extracts of Eucommia ulmoides(E.ulmodies)leaves was studied scrupulously and rationally.Meanwhile,the scale-up experiment in laboratory was conducted.The main results were shown as follows:(1)Quantitative detection method of CGAHigh performance liquid chromatography(HPLC)was used in this paper.The quantitative detection method of CGA from the crude extracts of E.ulmodies leaves was established and validated with methodologies.The results showed that the HPLC method could be used to quantitative analysis of CGA with its steady baseline,high separation and high average recovery.(2)Separating with macroporous adsorption resinADS-21 was selected as the best resin.And it had the maximum adsorption capacity,satisfying Langmuir equation and Pseudo-two-order kinetics equation at 25 ?.The optimum technological conditions of ADS-21 were: 1)adsorption: adsorption liquid at pH=2 and 25 ? with velocity of flow of 2 BV/h,sample concentration of 3.01 mg/mL and sample volume of 8 BV;2)desorption: elution velocity at 2 BV/h in the mixture of 3 BV ethanol with 40% concentration and 10 BV ethanol with 50% concentration.The purity of chlorogenic acid would increase 7.62 times from 5.01% to 38.1% and the rate of recovery is 92.8%.(3)Purifying with resin and silica gelFurther purification and enrichment with resin and silica gel for CGA was conducted.The optimum technological conditions to purify with silica gel was that solid-liquid ratio was M:V(g:m L)=1:100 when the chromatographic was D:H(cm:cm)=3.5:35.And the optimum technological conditions with X-5 resin was that solid-liquid ratio was M:V(g:mL)=1:10 and pH was 6 when the chromatographic was D:H(cm:cm)=3.5:35.The purity of CGA would raise to 73.2% from 38.1% and yield will be 65.3% after purification with resin and silica gel.(4)Decoloring and purifying with activated carbonThe optimum technological conditions to decolor and purify with activated carbon was: 1)adsorption: 200 mesh powder activated carbon,temperature at 30 ?,solid-liquid ratio M:V=2:50(g:mL),and duration of 1.5 h;2)desorption: temperature at 50 ?,ethanol concentration of 50%,duration of 5 h,desorption quantity of 7 BV and repeated three times.Near colorless CGA product would be got,the purity would raise to 93.4% and yield would be 88.7%.(5)Scale-up experiment in laboratoryThe results of the scale-up experiment in laboratory showed that the purity and total yield is 92% and 60%,consistenting with the results of the preliminary experiment.The extraction technology was stable,reliable and it is applicable to industrial preparation of highly pure chlorogenic acid from crude extracts of E.ulmodies leaves.