Establishment Of The Analytical Method Of Flavonoids Compounds In Tartary Buckwheat

Tartary Buckwheat (Fagopyrum tararicum), is a crop in our country,and is cultivated widely inNeimeng, Gansu, Ningxia, Sichuan, Guizhou, Yunnan, Shanxi and other places. Tartary Buckwheat hashigh nutritional value, in which the contents of protein, fat, vitamin and trace elements are all above thecontent of which in wheat, rice, millet, sorghum, maize etc. Above all, it contains flavonoids compoundswhich do not appear in other cereals. All of those nutrients play an extremely important role in humanbeing's metabolism. Tartary Buckwheat produced in Sichuan in 2008 was used as experiment materialfor the study. The objection of this study is to establish extraction, purification and determinationmethods for determining flavonoids in buckwheat and for the intensive study of the Tartary Buckwheatand its products .Four conventional extraction methods including ultrasonic and shaking with an constanttemperature in water bath were compared. Optimization of extraction parameters of ultrasonic andshaking methods were intensively studied. Optimal extraction parameters of the shaking method, suchas extraction solution (80% ethanol), liquid-to-solid ratio (30:1), 3 h, 60℃, were obtained; Theultrasonic extraction method's parameters were 80% ethanol as extractor, liquid-to-solid ratio=40:1, 3 hextraction under 60℃. The discrepancy in the content of flavonoids extracted with the two methods wasnot significant. Therefore, the ultrasonic extraction method with time saving advantage was used forfurther purification and determination studies.By optimizing the ratio of methanol and water, pH, chromatograph column, flow rate and columntemperature, a HPLC method for determining the contents of rutin, quercetin and kaempferol wasdeveloped and validated. The results of the stability and recovery test demonstrated that this paperprovided a feasible and reliable method for flavonoids in Tartary Buckwheat.Purification test by macroporous resins showed that HPD100 macroporous resins was superioramong four kinds of resins in adsorption and desorption properties in a static-absorption test. Optimalparameters were set up as:adsorption flow rate was 2 mL/min, the desorption flow rate was 3 mL/min,the concentration of ethanol was 70% and the volume of the desorption fluid was 3 BV.Three kind of flavonoids in buckwheat was identified with UPLC-MS, and a quantitive methodwas established;Qualitative analysis with HPLC-Tof/MS of quercetin-3-rutinoglucoglucoside,kmaepferol-3-rutinoside,hyperoside,quercetin-7-O-rhamnoside or kmaepferol-3-O-heteroside werefound in Tartary Buckwheat.