Extraction And Purification Of Chlorogenic Acid Of Lonicera Japonica And Process Optimization

Chlorogenic acid is a kind of phenylpropanoid substance produced by the process of aerobic respiration of plants.It mainly exists in Lonicera Japonica Thumb,Chrysanthemum and Eucommia.A large number of studies have shown that chlorogenic acid has many biological activities,such as antibacterial,anti-virus,anti-tumor,cardiovascular protection and so on.It has been widely used in medicine,health products,food and cosmetics industries.There are many ways to extract chlorogenic acid in Lonicera Japonica Thumb,including ultrasonic method can not only shorten the time,save solvent,improve efficiency,but also can avoid the high temperature of chlorogenic acid damage.Therefore,this method is selected to extract chlorogenic acid.This paper studies the extraction and separation process optimization of chlorogenic acid in Lonicera Japonica Thunb and an effective green technology is established.First of all,the chlorogenic acid from Lonicera Japonica Thunb was extracted by ultrasonic wave,and five groups of single factor tests were researched in this article,such as pH,extraction time,ethanol concentration,solid-liquid ratio and extraction temperature.The response surface methodology was used to optimize the design of four factors which had great influence on the experimental results by Design-Expert software,so as to determine the optimal extraction conditions.Then,the macroporous resin was used to separate the crude extract of chlorogenic acid,and the effects of many factors were investigated through static and dynamic experiments,including resin type,sample volume,sample flow rate,sample concentration,pH,the choice of eluent and elution flow rate.Finally,the chlorogenic acid was further purified by the method of ethyl acetate extraction and recrystallization,and the effects of three factors were investigated,including solution concentration,pH and extraction times.The analysis of chlorogenic acid was studied by HPLC and nuclear magnetic resonance.The main experimental results were as follows:1.The optimum technological conditions of ultrasonic extraction was as follows: the pH of extraction solvent was 5.2,the extraction time was 21 min,the ethanol concentration was 63%,the solid-liquid ratio was 1:13.5,the extraction temperature is 25℃.Under the optimal conditions,the extraction yield of chlorogenic acid was 10.862%.2.The optimum technological conditions of macroporous resin separation was as follows: the type of macroporous resin was NKA-9,the volume of sample solution was 35 mL,the flow rate of sample solution was 1mL/min,the concentration of sample solution was 4.5mg/mL,pH value was 4,the choice of eluent was 50%,the flow rate of elution was 3mL/min.Under the optimal conditions,the purity of chlorogenic acid was 78.62% and the total yield was 83.36% by HPLC.3.The optimum technological conditions of the purification of chlorogenic acid was as follows: the concentration of sample solution was 7.5mg/mL,pH value was 3.5,the extraction times was 3.The purified chlorogenic acid was detected by HPLC,and the purity of chlorogenic acid was increased from 78.62% to 91.33%,so the purification effect was very obvious.Finally,the purified product was identified by nuclear magnetic resonance(NMR),and it was proved that the compound was chlorogenic acid.