Preparation And Protein Self-assembly Of Myricetin

Myricetin has broad application prospects for hypoglycemic effect,antitumor,antibacterial,antiviral antioxidative and other biological activity.However,myricetin can't be wildly applied for its scarce natural resources and poor bioavailability.In order to expand its application in medical field,myricetin was prepared by chemical method and the dosage form of myricetin was improved.In this study,the synthetic method of myricetin was explored and the structure of reaction product was confirmed by HPLC and NMR.Resourceful dihydromyricetin and sodium thiosulfate were separately used as raw material and dehydrogenating agent.The preparation conditions were optimized by myricetin yield and optimum reaction conditions were as follows: reaction temperature of 85 ?,reaction time of 13 h,mole ratio of sodium thiosulfate and dihydromyricetin of 0.65 and solvent dosage of 9.48 mg/mL.As a result,the yield of myricetin was 87.68% and the purity was 96.81%.To improve the bioavailability of myricetin,casein-myricetin nanoparticles were prepared by molecular self-assembly method and the structure of drug loaded nanoparticles were characterized by ultraviolet spectroscopy and infrared spectroscopy.The reaction conditions were optimized by particle size,encapsulation efficiency and drug-loading rate,optimal reaction conditions were pH of 5.5,casein concentration of 2 mg/mL,mass ratio of casein and myricetin of 8:1,ultrasonic power of 300 W,ultrasonic time of 5 min and ethanol volume of 7 mL.The hypoglycemic effect of myricetin was studied using diabetic mice model,results show that general life situation and important physiological and biochemical parameters were determined by giving different doses of myricetin and the hypoglycemic effect of prepared myricetin was in accordance with myricetin standard sample.Rat intestine perfusion was also studied to investigated the bioavailability of casein-myricetin nanoparticles,the results showed that casein-myricetin nanoparticles can be more easily absorbed by small intestine than myricetin standard sample and prepared myricetin.