The Kinetics And Thermodynamics Research Of The Extraction Of Flavonoids From Radix Astragali Based On HSDE

As the modernization of traditional Chinese medicine develops,traditional Chinese medicine extracts which is an important step of sample pre-preparations has aroused more attention.Extraction efficiency is very important while extracting process is also a primary one which is the important criteria for time-effectiveness relationship.This thesis takes flavonoids in Radix Astragali as the object of research,make HSDE as its approach.In this paper,the main discussion was centered on extracting method,dynamics,thermodynamics.The content of this dissertation are the following:1.It compared the extraction efficiency of ultrasonic extraction and the extraction efficiency of HSDE.Make the extraction efficiency of Calycosin-7-O-?-D-glucoside,Calycosin,Formononetin,Ononin as the evaluation index.The results demonstrate that HSDE is superior to ultrasonic extraction in the condition of using methanol as solvent.2.Through extraction conditions selection and optimization.The method for Chinese herbal medicines extracted by HSDE was presented.Methods taking the extraction efficiency of the Calycosin-7-O-?-D-glucoside,Calycosin.Formononetin,Ononin as index.The optimal extraction conditions were selected by single factor experiments of solid-liquid ratio,extraction time,rotate speed and L9(34)orthogonal experiments,which included the solid-liquid ratio of 1:20,180 s extraction time and rotate speed of 16000 rpm.Experimental results prove that this method is simple,fast and accurate.3.Based on extraction mechanism of HSDE and the diffuse theory.This study research on the dynamics about Calycosin-7-O-?-D-glucoside,Calycosin.Formononetin.Ononin.Set the sampling time at 0 s?30 s?60s?90s?120 s?150s?180s.Drawing the time-effectiveness curve and suitable kinetics models of HSDE.Taking time as horizontal axis and the ratio of time to peak area as the longitudinal axis,the data is linearly fitted.The equations are Calycosin-7-O-?-D-glucoside:y=0.00974x+0.00869,R2=0.99736;Calycosin:y-0.00153x+0.01654.R2 ?0.9862;Formononetin:y = 0.00196 x +0.02322,R2 = 0.98492;Ononin y = 0.00527 x+0.046,R2 = 0.99228.The results show that the HSDE extraction process of the four kinds of flavonoids compounds from Raidx Astragali follows the pseudo-second-order equation.It is inferred that the extraction mechanism involves the cooperative action of cavitation effect,mechanical effect and shear effect.4.Based on the Second Law Fick diffusion.The model of HSDE extraction is proposed.Make the pellet particle size,evenness,diffusion coefficient as the parameter.The thermodynamics equations of flavonoids was set up.And rate constant k,activation energy Ea,enthalpy change ?H0,entropy change AS and free energy change ?G0 were calculated.This study has prompted speculation about extracting process and thermal motion of the microcosmic molecule.On the basis of the results of our experiments,simulation results show that there is similarity in extracting process at different temperatures.With the temperatures increasing,extraction efficiency improved.That raises the temperature of system,material that heat moves heighten,accelerating the crucial step of extraction.And strive to play the role of endothelial surface diffuse.In view of significant advantages of HSDE against conventional extraction techniques.The platform of sample pre-preparations use HSDE was established in this study and expected can be applied to other Chinese crude drugs.The paper investigated the kinetic and thermodynamic theories.This has provided new method and idea for the extraction technology and pretreatment method for medicinal materials.