Study On The Extraction Technology Of Chlorogenic Acid From Dandelion Leaves And Its Decreasing In Vitro

Dandelion is an important clinical herbal medicine.Its resources are abundant,the source is extensive,the price is low,mainly contains flavonoids,polysaccharides,pigments,organic acids.Dandelion acid has antibacterial,anti-virus,blood pressure lowering,anti-cancer effect.The content of chlorogenic acid in dandelion is rich,especially in dandelion leaves,but the effect of chlorogenic acid in dandelion leaves on lowering blood lipid is less studied.Therefore,the chlorogenic acid in dandelion leaves was extracted,the macroporous resin method was used to further separate and purify the dandelion extract,and the high purity chlorogenic acid crystal was obtained after recrystallization.And through its binding ability with different kinds of sodium cholelithiasis salt,evaluate its lipid-lowering function in vitro,open a new market for more comprehensive development and utilization of dandelion.The main studies are as follows:(1)Extraction of chlorogenic acid from dandelion leavesThe optimum extraction process of chlorogenic acid in dandelion leaves was selected by traditional ethanol reflux method and ultrasonic assisted extraction method.Finally,the ultrasonic assisted extraction method with higher extraction rate of chlorogenic acid was determined to extract chlorogenic acid from dandelion leaves Line extraction.And the time is short,the efficiency is fast.On the basis of single factor test,the factors and levels of the test were selected.The yield of chlorogenic acid in the extract was studied by response surface design method to determine the best extraction process.The results showed that the optimum extraction conditions were: ratio of material to liquid 1:16(g/m L),volume fraction of ethanol80%,ultrasonic extraction temperature 60℃,ultrasonic power 50 W、 ultrasonic frequency60 KHz;Under these conditions,the yield of chlorogenic acid in dandelion leaves could reach28.56 mg/g.It provides a broad market for the extraction and development of chlorogenic acid in dandelion leaves in the future.(2)Chlorophyta in dandelion leaves Separation and purification of acidsThe adsorption rate and desorption rate of chlorogenic acid in dandelion leaves were studied by macroporous resin D1300、 macroporous resin HZ-816、 macroporous resin NKA-9 and the optimal macroporous resin was selected to purify chlorogenic acid in dandelion leaves.On the basis of single factor,the purification process of chlorogenic acid in dandelion leaves was optimized by response surface method.The results showed that the optimum purification conditions of chlorogenic acid in dandelion leaves were as follows:flow rate 2.0 BV/h;concentration 2.0 mg/m L;volume 5.0 BV;elution condition The flow rate of eluent is 2.0 BV/h;the concentration of eluent is 50% ethanol,the volume of eluent is4.0 BV.Green primary acid yield in dandelion leaves: 17.31 mg/g.(3)Characterization of chlorogenic acid in dandelion leavesThe chlorogenic acid in dandelion leaves was identified by UV,IR and HPLC/MS.The results showed that there was chlorogenic acid in dandelion leaves.(4)Study on the in vitro lipid-lowering activity of chlorogenic acid in dandelion leavesBy simulating the gastrointestinal environment,The hypolipidemic function of two kinds of sodium cholic acid and chlorogenic acid in dandelion leaves was evaluated by combining ability.The results showed that chlorogenic acid and sodium cholic acid in dandelion leaves had higher binding ability and obvious hypolipidemic function.It provides a broad market for the development of hypolipidemic functional products of chlorogenic acid in dandelion leaves in the future.