Abstract: To determine the content of proantho cyanidins B₂ in Fagopyrum dibotryis superfine powder, the Fagopyrum dibotryis crushed less than 0.75 nm superfine powder extracted by 50% ethanol,an HPLC method was used. Epicatechin showed a good linear relationship in 0.0352 to 1.4080 μg/mL and the regression equation was Y=59797X+592.3,r=0.996. Proantho cyanidins B₂ of Fagopyrum dibotryis superfine powder content was between 1.305 to 1.541 mg/g.The method was simple and suitable for determing the content of proantho cyanidins B₂ in Fagopyrum dibotryis superfine powder. It provided the scientific basis for Fagopyrum dibotryis preparation quality control.

Key words: Fagopyrum dibotryis; superfine powder; HPLC; proantho cyanidins B₂