Determine Proanthocyanidins in Grape Seed Extract with Proanthocyanidin B2 Standard

To establish a method for detecting proanthocyanidins in grape seed extract with proanthocyanidin B2 standard.Refer to the Bate-Smith method,using proanthocyanidin B2(≥99;HPLC) to calibrate proanthocyanidins in grape seed extract at 546 nm.Linear range of proanthocyanidins is 22.89 μg/mL-114.5 μg/mL(r=0.999 02,n=5),Recovery∶97.99 %,RSD∶1.02 %(n=6).Using single ingredient proanthocyanidin B2 standard calibrated by HPLC to calibrate proanthocyanidins,resolving the problem that the standard content is not identical and can not convince when using proanthocyanidin compound standard.The method have better linearity and repeatability,can detect grape seed extract's proanthocyanidins exactly.