Extraction,purification and anti-hyperlipidemic activities of total flavonoids from corn silk

In this study,some important parameters were optimized for effective extraction and purification of total flavonoids from corn silk,and the anti-hyperlipidemic activities was analyzed in rabbits by feeding experiment. firstly,the high extraction yield (5.32 mg·g-1) of total flavonoids were obtained under the optimal extraction conditions,which are 80°c for 3 h with corn silk over 60% ethanol ratio of 1:30. then,the ab-8 resin was selected for the purification of flavonoids due to the higher static adsorption and adsorption capacity than other resins. the optimum conditions for purifying flavonoids as follows: for adsorption,sample concentration was 2.542 mg·ml-1,ph was 3.7,processing volume was 4 bv; flow rate was 2 bv·h-1; temperature was 25°c. for desorption,elution solvent ethanol-water (95%,v/v) solution was 4.5 bv; flow rate was 2.0 bv·h-1. flavonoids with content of 68.3% were obtained with a flavonoid recovery of 93.7%. the results showed that ab-8 resin revealed a good ability to purify total flavonoids. lastly,feeding experiments results indicated that flavonoids had significant anti-hyperlipidemic activities to rabbits by reducing the content of serum total cholesterol (tc),triglycerides (tg),and low-density lipoproteincholesterol (ldl-c) and increasing the concentration of high-density lipoprotein-cholesterol (hdl-c). copyright 2017 zoological society of pakistan.