Study On The Preparation And Activity Of Water-Soluble Luteolin

Luteolin is a poorly water-soluble flavonoids.In order to improve the water solubility of luteolin,the luteolin is modified to improve the water-soluble.Obtained the solid lipid particles and luteolin solid dispersion.It is determined by single factor and response surface experiment to determine the best process for their preparation.Micromorphological observations and structural characterizations of the two modified products were performed,Meanwhile,two kinds of water-soluble luteolin antioxidant capacity and inhibition of nitrosation were studied(1)Luteolin solid lipid particles were prepared by thin film ultrasonic method.With the encapsulation rating and sample loading as the evaluation index,the optimal preparation condition of luteolin solid lipid particles was determined by single factor and response surface experiments.The raw material dosage was 20.72 mg,and the mass ratio of stearic acid to lecithin was 1:2,ethanol volume fraction 71.48%,Tween dosage 15.82mL,The lyophilized protective agent was lyophilized with 5%mannitol.The final evaluation index of luteolin solid lipid particles was up to 71.86%.(2)The luteolin solid dispersion was prepared by melting method.The cumulative dissolution was used as the inspection index.The optimum preparation process of luteolin solid dispersion was determined by single factor and response surface experiments:raw material dosage was 39.43 mg,raw material and carrier mass ratio was 1:5,preparation time was 30.78 min,preparation temperature was 70.98?,and the obtained luteolin solid was obtained.The cumulative dissolution of the dispersion reached 83.50%(3)The maximum absorption wavelength of luteolin was measured by ultraviolet spectrum scanning at 353 nm;The characteristic absorption peaks of the infrared spectrum showed that no new chemical bonds were formed during the preparation of luteolin solid lipid particles and luteolin solid dispersions.The distribution of luteolin solid lipid particles was uniform and spherical under transmission electron microscope.The results of scanning electron microscopy showed that luteolin was present in the solid dispersion of luteolin in a smaller crystallite or amorphous crystal.Differential scanning calorimetry results obtained that both modified products exist in amorphous form;The solubility and oil-water partition coefficient of luteolin,luteolin solid lipid particles,and luteolin solid dispersion were measured.The results showed that the two modification methods effectively improved the water solubility of luteolin(4)Ascorbic acid as a control.The antioxidative activities of luteolin and luteolin-water-soluble modified products were studied from four aspects:DPPH�radical,hydroxyl radical,superoxide anion scavenging ability and total reducing ability.The order of magnitude of the antioxidant capacity obtained is:Ascorbic Acid>Luteolin Solid Dispersion>Luteolin Solid Lipid>Luteolin.(5)Under simulated human gastric juice conditions,Through the scavenging effect of NaNO2,the blocking effect of N-dimethylnitrosamine(NDMA)and the ability of preventing nitrate reductase from reducing NO3-to NO2-,the water-soluble modification of luteolin and luteolin was investigated.The product inhibits the activity of the nitrosation reaction.The results showed that the order of inhibition of nitrosation was:luteolin solid dispersion>luteolin solid lipid particle>luteolin.