Ethyl acetate extract was used for HPLC/DAD analyses,
made according to a protocol devised by Peng and coworkers
to analyze procyanidins in grape seeds [23]. Electrospray
LC/MS analysis was made with a reverse phase
RP-18 column (125 × 2 mm, 5 μm particles). Elution was
achieved with solvents A (0.05% TFA in water) and B (acetonitrile),
linear gradient from 0 to 50% B in 20 min, held
isocratic at 50% B up to 45 min and then reduced to 0%
B from 45 to 55 min. Flow rate was 1 ml/min and 5 μl of
sample were injected. The apparatus was operated in positive
mode, scanning from 300 to 2000 amu. Mass chromatograms
were also obtained by monitoring peaks between
masses 550–600, 850–900 and 900–2000 amu.