Extraction And Purification Of Flavonoids From Corn Silk And Its Hypoglycemic Effect

Flavonoids are the main bioactive components of corn silk,with a variety of pharmacological values.In this study,corn silk was used as the research object to extract,purify and optimize the related technology of flavonoids.Then,the effect of flavonoids from corn silk on hypoglycemic was studied by cell experiments.The results were as follows:1.Extraction of flavonoids from corn silk with solvent.The extraction process was optimized by single factor and orthogonal experiment,and the optimum parameters was 60% ethanol at 60 ?for 2h,solid liquid ratio 1:20.The yield of flavonoids was 1.536% under the optimum conditions.2.Ultrasonic-assisted extraction of flavonoids from corn silk.The extraction process was optimized by single factor and orthogonal experiment,and the optimum parameters ware 60% ethanol at 400 W for 20 min,solid liquid ratio 1:20.The yield of flavonoids was 2.263% under the optimum conditions.3.Microwave extraction of flavonoids from corn silk The extraction process was optimized by single factor and orthogonal experiment,and the optimum parameters was 70 ? for 8 min,solid liquid ratio 1:50.The yield of flavonoids was 1.847% under the optimum conditions.4.The results show that the ultrasonic-assisted method and the microwave-assisted extraction method are better than the solvent extraction method.Ultrasonic-assisted method is the highest method in the three methods.5.The best conditions for the purification were as follows: p H = 3,ethanol concentration 60%,flow rate 1.0m L / min,elution volume 5BV,The adsorption rates of flavonoids in solvent,ultrasonic-assisted and microwave were 70.32%,85.16% and 72.08%,respectively.6.HepG2 cells were cultured in different flavonoids,measuring the consumption of glucose in cultured and the activity of triglyceride(TG),glucose-6-phosphatase(G-6-Pase)and glucokinase(GK),the expression of Hep G2 cells have the ability to consume glucose in the culture fluid,inhibit the TG and G-6-Pase decomposition,and increase the activity of GK,so different extraction of flavonoids have hypoglycemic effect,but also have different effects on indexes,microwave method > ultrasonic method > solvent on the consumption of glucose,microwave method < solvent method < ultrasonic method on TG,solvent method < microwave method < ultrasonic method on G-6-Pase,ultrasonic method > solvent method > microwave method on GK.In summary,the microwave extraction of corn flavonoids hypoglycemic effect is relatively obvious.7.Corn silk flavonoids purification by HPLC,compared with the standard spectrum,the results showed that there were three kinds of monomer substances,which were luteolin,miscanthus and rhamnolipid.In this study,maize flavonoids were extracted and purified,and the process parameters of different methods were determined.In vitro,the hypoglycemic effect of corn flavonoids was discussed by cell experiment,which laid the foundation for further research,development and utilization of corn flavonoids.