Study On The Process And Process Of High Purity Isoquercitrin In Wasted Mulberry Leaves

As"medicine and food homologue",mulberry leaves have extremely high pharmacological value.Because of the mode of production and operation,there are problems such as low utilization rate,resulting in the loss of high value-added components and the waste of mulberry resources.In this paper,the old mulberry leaves or wasted mulberry leaves are used as raw materials,andintroduced the hydrothermal reaction into the natural product extraction technology,carry out the extraction of high-purity and high value-added isoquercitrin and other active ingredients.To realize the value-added development and high-value utilization of mulberry resources.At the same time,turn abandoned mulberry leaves into valuable products,in line with the national resource depletion and"national health"strategy.In order to improve the effective dissolution of active ingredients such as isoquercitrin,using hydrothermal reaction method,evaluate the effects of hydrothermal time,solid-liquid ratio,hydrothermal temperature and ethanol volume fraction on the dissolution of isoquercitrin.Optimization of the parameters of hydrothermal-assisted alcohol extraction of isoquercitrin from mulberry leaves by response surface methodology.SEM,BET and FTIR were used to analyze the phase structure and composition changes of mulberry leafves tissue before and after hydrothermal reaction,explore the properties of hydrothermal degradation of plant tissues.In order to further reveal the restrictive factors and mass transfer laws of isoquercitrin leaching,the kinetic parameters such as mass transfer coefficient k,activation energy Ea,relative vacancy rate y and effective diffusion coefficient Ds were calculated,Study on the kinetics of isoquercitrin leaching using Fick's second law.Analyzed the diffused process of isoquercitrin with different particle sizes,established an internal diffusion model of isoquercitrin,and obtained the diffusion rate constant of isoquercitrin.In order to obtain isoquercitrin with high-purity,the mobile phase composition,its ratio,flow rate and injection amount were compared to prepare conditions for separation and purification of isoquercitrin,and analyze the beneficial result.conclusion as below:?1?The suitable parameters for the extraction of isoquercitrin by hydrothermal reaction assisted alcohol method using response surface methodology are as follows:with a volume fraction of 57%ethanol as the extractant,the ratio of mulberry leaf mass?g?to ethanol volume?v?was 1:7,hydrothermal temperature is 154?and hydrothermal time is 80 min,could extract the content of isoquercitrin was 3.6491mg�g^-1,It is about 51 times that of ethanol.The equation for the immersion of isoquercitrin was obtained by the response surface method,the value of R² is 0.9582,F is 22.91,P<0.0001,which indicates that the model is available.According to the F value,obtained the order of influence of the four factors is:hydrothermal time>hydrothermal temperature>liquid-to-liquid ratio>ethanol volume fraction,The interaction between hydrothermal time and hydrothermal temperature has a significant effect on the amount of isoquercitrin.The mulberry leaf extract showed the antioxidant capacity at a lower concentration of 0.02 mg�mL^-11 by the DPPH clearance rate,superoxide anion clearance rate,lipid peroxidation inhibition rate and reducing ability,a positive correlation was observed in the concentration range of 0.02 mg�mL^-11 to 0.1mg�mL^-1.?2?The results of FT-IR indicated that the hydrothermal reaction contributed to the C-O,C-H,C=C bond cleavage in mulberry leaves,and promoted the decomposition of phenylpropane structural unit in mulberry leaf lignin.The results of SEM showed that the pores between the mulberry leaves become larger and the pores appear.The results of BET showed that the specific surface area of the substrate after hydrothermal reaction is higher than that of the raw material,indicating that the hydrothermal reaction can effectively degrade the fiber tissue of mulberry leaves,which is beneficial to the dissolution of natural active ingredients.The diffusion model of particle shows that there are three processes,is permeation,internal diffusion and boundary diffusion in the diffusion of isoquercitrin,the thickness constant C of the boundary layer is C_I<C_II<C_III,the rate constant of diffusion k becomes smaller as the thickness of the boundary layer increases.?3?According to Fick's second law,obtained the kinetic model of immersion of mulberry leaf isoquercitrin.When the temperature is between 120�C and 160�C,calculated the rate constant k is from 0.0157 min^-11 to 0.0301 min^-1,the apparent activation energy Ea is 27.22 kJ�mol^-1,and the pre-exponential factor A is 0.0164 min^-1,and the smaller the apparent activation energy is,which is beneficial to the reaction.The effective diffusion coefficient Ds is 0.52�10^-4mm²�min^-10.99�10^-4mm²�min^-1,and increased with increasing temperature.The raffinate rate decreased with increasing temperature,the minimum raffinate rate at 154?is 9.75%,At this time,the leaching rate of isoquercitrin is 91.25%.The thermodynamic analysis determined that?Gm was-4.3743kJ�mol^-1-1.2582kJ�mol^-1<0,?Hm=34.907kJ�mol^-1>0,?Sm=92.47J�mol^-1>0,indicating that the process of hydrothermal assisted alcohol extract isoquercitrin is a spontaneous process of endothermic entropy increase.?4?Purified by preparative chromatography to obtain isoquercitrin,the suitable conditions of separation and purification were:the ratio of the volume of acetonitrile to water is 20:80,the volume is 10mL,the flow rate is 20mL�min^-1.After lyophilization,the preparation rate of isoquercitrin was 26.36%,and the purity was 98.78%.At the same time,the preparation rate of chlorogenic acid was 30.37%,the purity was 99.47%,the preparation rate of rutin was 19.51%,the purity was 98%,the preparation rate of astragalin was 11.47%,and the purity was 98%.