| Blueberry anthocyanin is kind of natural antioxidant,which is widely used in the fields of food and medicine.Anthocyanins are sensitive to temperature,light and humidity.Moreover,the polarity of anthocyanins is strong,and the solubility is very small,which greatly limits its application.It is necessary to increase the stability and lipid solubility of anthocyanins.In this study,the water soluble oil microemulsion was prepared,and its quality stability and antioxidant activity in vitro were studied.On the one hand,through solubility experiment,blank microemulsion oil phase was selected by pseudo three dimensional phase diagram method,with the area of microemulsion as indicators.Under different moisture content,viscosity,conductivity,refractive index and density were measured,the configuration of micro emulsion and the best conditions microemulsion were determined.On the other hand,with the extraction rate as index,effects of solid-liquid ratio,ethanol concentration,microwave power and time on the extraction rate of blueberry anthocyanins were studied,and the optimum extraction process through the optimization of response surface was confirmed.With the adsorption rate and desorption rate as the index,the type of resin,the purified anthocyanin concentration of sample,the temperature of sample,the eluent concentration and elution velocity of purified liquid were determined.Finally,the anthocyanins were embedded in micro-emulsion,and the micro-emulsion particle size and morphology were characterized by particle size analyzer and transmission electron microscopy.The stability under light and temperature were measured.Through the DPPH radical scavenging,the superoxide anion radical scavenging ability and ABTS experiment,determinded the stability of the microemulsion package and the antioxidant activity of anthocyanins and buried.The results showed that the isopropyl myristate as oil phase,surfactant Tween 80/span 80 compound agent,anhydrous alcohol as co-surfactant,if and only if HLB=7.5 and Km=2:1,the area of micro-emulsion was largest,the quality of microemulsion was better when the mass ratio of oil phase and emulsifier was 7:3.The best extraction process parameters of blueberry anthocyanins:ethanol concentration was 60%,microwave power was 285 W,microwave time was 88 s,solid-liquid ratio was 1:31.4.In the conditions,the anthocyanins extraction rate was 94.03%;the optimal parameters for the purification of anthocyanins:temperature was 30,pH3,the concentration of sample was 1.4 mg/L,elution rate was 2.5 mL/min with 60%ethanol as eluent.According to the optimized microemulsion formulation and the separation process of blueberry anthocyanins,the preparation of anthocyanin microemulsion.And its quality and antioxidant activity was evaluated in vitro.The appearance of the anthocyanin microemulsion was dark red,clear and transparent,and stable in nature.Under the transmission electron microscope,it was observed that the droplet was spherical,and the particle size was between 1?100 nm.It was W/O microemulsion that proved by staining method,its viscosity was 39.87 mpa/s with the rotation viscometer,and the conductivity was measured to be 37.62 s.cm-1.Through the scavenging of DPPH radical,ABTS radical and superoxide anion,the IC50 of the microemulsion was 27.1,23.4 and 18.5 mg/L.In summary,the stability and functional activity of anthocyanins obtained by this method can be improved to a certain extent.This provides a theoretical reference for the development of anthocyanin related products. |
PDF Full Text Request