Preparation And Structural Characterization Of Ginger Essential Oil Liposomes

In this study,lecithin(LT)andβ-sitosterol(β-S)were used as wall materials,and ginger essential oil(GEO)was embedded by ethanol injection method-ultrasonic method to prepare ginger essential oil liposomes(GEO-L),so as to control the release of GEO,improve the stability and utilization of GEO,and expand the application scope of GEO.The main research is as follows::1.The effects of different LT andβ-S mass ratios,LT and GEO mass ratios,rotary evaporation temperature,ultrasonic power and ultrasonic time on the encapsulation rate of the prepared GEO-L were investigated,and the optimal The range of preparation conditions;the optimal process parameters determined by the response surface experiment optimization are:the mass ratio of LT toβ-S is 3.1:1,the mass ratio of LT to GEO is 4.6:1,the ultrasonic time is 35.6min,and the ultrasonic power is 815k W.Under the optimal process conditions and the temperature of rotary steaming is 40℃,the embedding rate of the prepared GEO-L reaches 81.092%.LT,the assembly polymer of LT andβ-S(LT-β-S)and GEO-L were analyzed for particle size,and the shape and color of GEO-L were observed.The results showed that the average particle size of GEO-L prepared by wall embedding was 0.309±0.001μm.In addition,due to the addition of GEO,the specific surface area of GEO-L was significantly reduced from 12.200±0.134 m~2/g to 6.892±0.022 m~2/g compared with blank liposomes;Appearance,it can be seen that the liposome emulsion with GEO embedded is yellow,and the color is lighter,and there is no obvious delamination or coagulation,and it is in a uniform state;The color of GEO-L liposomes in the freeze-dried state was slightly yellow,and the results were soft and dispersed,and there was no obvious moisture absorption and agglomeration..2.Freeze-dried GEO-L was obtained by vacuum freeze-drying the GEO-L emulsion prepared under the optimal preparation process conditions.The physicochemical properties of GEO-L were determined by moisture content,hygroscopicity,wettability and solubility.The particle morphology of liposomes was observed by scanning electron microscopy(SEM)and transmission electron microscopy(TEM),and the LT,β-S,LT-β-S assemblies and GEO-L were analyzed by Fourier transform infrared spectroscopy(FTIR).The assay analysis was performed,and the thermal stability of the physical mixture,LT-β-S blank liposomes and lyophilized GEO-L was tested by X-ray diffractometer(XRD)and thermogravimetric analysis(TGA).The SEM results showed that the liposomes were spherical or quasi-circular,and the size was relatively uniform,and the freeze-dried liposomes appeared adhesion due to the wall material and drying method;TEM results showed that the liposomes in the liquid state presented Uniform,circular,and evenly dispersed,with a smooth structure surface;FTIR results showed that GEO had been embedded in liposomes,indicating that the liposome structure was effective;TGA results showed that the liposome structure played a certain role in GEO.Thermal protection can effectively prevent the volatilization of GEO;XRD results show that the liposomes have a more compact structure.The results of DPPH free radical scavenging ability showed that GEO-L and the same concentration of GEO had no significant difference in DPPH free radical scavenging ability,showing good antioxidant ability.3.The in vitro sustained-release simulation experiment was used to study GEO-L.According to the particle size and Polymer dispersity index(PDI),the performance of GEO-L in the simulated gastrointestinal fluid was determined and the sustained-release curve was prepared to explore the simulation of GEO-L.Stability and bioavailability in in vitro digestion.The experimental results show that GEO-L has no significant changes in particle size and PDI in simulated gastric juice,and is relatively stable;while in the simulated intestinal juice,a digestion reaction occurred,and the final cumulative release rate of GEO reached 87.06%.The results of the scavenging ability of DPPH free radicals showed that GEO-L and the same concentration of GEO had no significant difference in the scavenging ability of DPPH free radicals,showing good antioxidant capacity.4.The changes of GEO-L under different storage conditions at different temperatures(4℃,25℃and 50℃),light and dark were studied,and the thiobarbituric acid(TBA)test was used to study the storage period of GEO-L of the oxidation conditions.The experimental results show that comparing GEO-L at the same temperature for different periods of time,GEO-L stored at 4℃shows better stability;GEO-L stored at the same temperature and protected from light The stability of MDA is better than that under light conditions;TBA experiment results show that GEO-L stored under 50℃and 25℃light conditions has a significant increase in MDA content,but it will not cause hemolysis..