[Determination of quercetin and kaempferol in Fagopyrum spp. of different species and different parts by HPLC].

OBJECTIVE:An HPLC method was established for determination of quercetin and kaempferol in Fagopyrum spp. of differrent species and different plant parts. METHODS:The chromatographic separation was carried out on a DIKMA diamonsil (250 mm x 4.6 mm, 5 μm) chromatographic column. The mobile phase was acetonitrile (A) and 0.1% phosphoric acid solution (B) at the flow rate of 1.0 mL/min. The detection wavelength was set at 260 nm and the column temperature was 25 degrees C. RESULTS:The descending order of quercetin content in the samples of different parts of Fagopyrum tataricum was seed (6.12 mg/g) > leaf (1.47 mg/g) > stem (0.34 mg/g); quercetin was not found in root. Only a few kaempferol was found in seed (0.42 mg/g) and leaf of Xiqiao 1 (0.09 mg/g) of Fagopyrum tataricum. There were a few quercetin was determined in the whole plant of Fagopyrum esculentum, and kaempferol was not been found. The total and mean value concentration of quercetin and kaempferol of Fagopyrum tataricum were much higher than that of Fagopyrum esculentum. In different species of Fagopyrum tataricum planted in the same area, the content of quercetin and kaempferol was similar, they were not been found in Fagopyrum esculentum. CONCLUSION:This method is simple, rapid, accurate and reliable for quality evaluation of Fagopyrum spp. and its commercial products.