文摘
The major constituents in grape seed and pine bark extracts are proanthocyanidins. To evaluatematerial available to consumers, select lots were analyzed using high-performance liquid chromatography, gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry(LC/MS), gel permeation chromatography (GPC), and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Atmospheric pressure chemical ionization (APCI)LC/MS was used to identify monomers, dimers, and trimers present. GC/MS analyses led to theidentification of ethyl esters of hexadecanoic acid, linoleic acid, and oleic acid, as well as smallerphenolic and terpene components. The GPC molecular weight (MW) distribution indicated componentsranging from ~162 to ~5500 MW (pine bark less than 1180 MW and grape seed ~1180 to ~5000MW). MALDI-TOF MS analyses showed that pine bark did not contain oligomers with odd numbersof gallate units and grape seed contained oligomers with both odd and even numbers of gallate.Reflectron MALDI-TOF MS identified oligomers up to a pentamer and heptamer, and linear MALDI-TOF MS showed a mass range nearly double that of reflectron analyses.