Qualitative and quantitative HPLC/MS determination of proanthocyanidins in areca nut (Areca catechu)

Proanthocyanidins (PACs) in areca nut (Areca catechu L.) were analyzed by high-performance liquid chromatography (HPLC) combined with electrospray-ionization mass spectrometry (ESI-MS) and compared to grape seed extract. Under optimized conditions, the separated PACs were individually analyzed and identified on the basis of their [M+H](+) peaks. The PAC distribution in areca nut was found to be very similar to that in grape seed, but lacking any gallate conjugates. Based on reverse-phase HPLC separation, the PAC monomers (+)-catechin (CA, 1) and (-)-epicatechin (EC; 2) were successfully quantified by ESI-MS in the selected-ion-monitoring (SIM) mode, (-)-epigallocatechin (EGC; 3) being used as internal standard. Detailed quality and validation assays showed that the accuracy and repeatability (n = 8) were within 10% for each analyte.