Cornus Officinalis Effective Components Extracted And Micro-Encapsulated By Supercritical CO₂

Cornus officinalis is a traditional medicinal plant of China,which is mainly in Henan,Zhejiang,Shanxi,Anhui,Sichuan and other regions.The nutritive components and physiological active functional substances in Cornus officinalis have high pharmacological value.In this study,the supercritical CO₂ extraction technology was used to extract the effective components from the Cornus officinalis and to study the microcapsules by a coaxial nozzle after mixing the self-made micro mixing chamber with the wall material.The extraction rate of Cornus officinalis was extracted by supercritical CO₂ fluid extraction.The effect of extraction temperature?308.15 K³28.15 K?,extraction pressure?10 MPa³0 MPa?,particle pulverization degree?40 order to 120 mesh?and entrainer concentration?0%⁶%?on extraction rate was studied.The results showed that:in the experiment,the extraction rate of Cornus officinalis was increased first and then decreased with the increase of extraction temperature.It increased with the increase of extraction pressure but increased slowly after 250 bar.With the increase of particle size,it increased first and then decreased,and increased first and then decreased with the increase of the concentration of the entrainer.The process optimization of four factors and five levels is designed by the response surface method.The two nonlinear regression equation model of the interaction between the extraction temperature,the extraction pressure,the particle smashing degree and the concentration factor of the entrainant is obtained:R=22.90+0.33A+0.28B+1.14C+1.74D-0.19AB-0.17AC+0.038AD+0.81BC+0.83BD-0.17CD-2.52A²-1.02B²-1.36C²-1.38D² and The optimum extraction conditions were extraction pressure 23.3 MPa,extraction temperature 320.45 K,concentration of entrainer 3.71%,particle pulverization degree 80 mesh,extraction rate of 23.54%.The composition of Cornus officinalis extracted by supercritical CO₂ was analyzed by GC-MS,and 17 chemical components were identified.On the basis of the extraction conditions of the effective components of Cornus officinalis after the response surface optimization,the average particle size of the microcapsules of the effective components of the Cornus officinalis was investigated as the index and the effects of CO₂ velocity?1.0 L/min³.0 L/min?,wall material flow velocity?0.5 mL/min to 2.5 mL/min?,nozzle diameter?50?m,75?m and 100?m?were studied.The results showed that the average particle size of microcapsules decreased first and then increased with the increase of CO₂ velocity and wall material solution flow rate,and increased with the increase of nozzle diameter.The orthogonal optimization experiment of three factors and three levels was designed to optimize the microcapsule preparation of CO₂ flow rate?A?,wall material flow velocity?B?and nozzle diameter?C?.The optimized process combination was A₃B₂C₁,that is,CO₂flow rate is 2.5 L/min,wall material flow velocity is 1.5 mL/min,nozzle straight diameter is 50?m,and microcapsule average particle size is 2.823?m.The microcapsules under optical microscope and scanning electron microscope showed many irregular shapes.The particle size was mostly 2.0 to 4.5?m,with adhesion and a small amount of cracks.