Study On Extraction Purification And Antioxidative Effects Of Flavoniods In Tatary Buckwheat Bran

The test used tatary buckwheat bran dry powder as material, mostly researched the extraction method of solvent, microwave and ultrasonic. The optimal parameters of these three extraction methods was identified by single factor and RSA experiment, at the same time, these three methods were compared. On the other hand, Coarse goods of flavonoids from tatary buckwheat bran was purified by macroporous resin and the purification parameters was determined by experiment. Finally,the antioxidant activity of samples was studied by seven different systems.The main results showed:1. The quantitative method for total flavonoids was researched.And then we detected the stability,precision and recovery of the method.2. The optimal parameters of solvent extraction from tatary buckwheat bran were as following: liquid to solid ratio 50:1, extracteing 4.8h and two times, pH10, temperature 67.2℃, ethanol concentration 60.1%.3. The optimal parameters of microwave extraction from tatary buckwheat bran were as following: soaking time 19.9min, microwave power 600W, extracted for 20min and one times, ethanol concentration 54.1%,liquid to solid ratio 34.7:1, borax content 0.002g.4. The optimal parameters of ultrasonic extraction from tatary buckwheat bran were as following: ultrasonic power 750W, extracted for 25.3min and three times, ethanol concentration 48.8%, liquid to solid ratio 24:1, pH 10.5. AB-8 macroporous resin had good performance of adsorption and deadsorption ability to flavonoinds.The optimum technological conditions were as follows: the pH of adsorbing stock solution 6.5, the dynamically adsorbing rate of flow 1 mL/min, the eluted alcohol concentration 70%, the eluted rate of flow 0.5mL/min(the ratio of diameter to high 1cm×40cm), and the content of flavonoids in elutriant was 95% through rotary evaporation conditons.6. Through a detailed analysis of color reaction and UV optical spectrum test of flavonoids, the flavonoids from tatary buckwheat bran. were primarily identified as flavonols.7. The vitro antioxidant activity of samples was studied by seven different system(O₂^-·,DPPH·,OH·,R·,NO₂^-, H₂O₂, deoxidant activity).The result showed that samples have certain the antioxidant activity and their antioxidant activity enhanced with the adding of concentration, Their antioxidant activity was different in different systems.