Profiles analysis of proanthocyanidins in the argun nut (Medemia argun--an ancient Egyptian palm) by LC-ESI-MS/MS.
Medemia argun is an ancient palm rich in proanthocyanidins (PACs). These polyphenolic compounds are widely distributed in plants and are an integral part of the human diet. A sensitive high-performance liquid chromatography and electrospray ionization mass spectrometry (HPLC-ESI-MS) method in the negative ion mode for sequencing these ubiquitous and highly beneficial antioxidants is described in order to profile different PACs in M. argun nuts. The analytical protocol based on tandem mass spectrometry was used to sequence dimers, trimers, tetramers and pentamers with different A-type, B-type and A/B-type linkages. Diagnostic ions resulting from heterocyclic ring fission and retro-Diels-Alder reaction of flavan-3-ol provided information on the hydroxylation pattern and the type of interflavan bond. The sequences were discovered through ions derived from quinone methide cleavage of the interflavan bond. The identification of PACs linkages through LC-MS(n) eliminates a number of tedious separation steps. The method was successfully applied to give a view of PAC profile in M. argun nuts. M. argun nuts contained 636.88 mg/g PACs (as equivalent of (þ)-catechin). The data obtained in our research show that M. argun is a rich source of hydrolyzable PACs.
Department of Botany, Faculty of Science, Aswan University, Aswan, 81528, Egypt; Department of Biochemistry and Crop Quality, Institute of Soil Science and Plant Cultivation, State of Research Institute, ul. Czartoryskich 8, 24-100, Pulawy, Poland.
Arafa I
AI
Hamed
Abdulla S
AS
Al-Ayed
Jaroslaw
J
Moldoch
Sonia
S
Piacente
Wieslaw
W
Oleszek
Anna
A
Stochmal
D028023:Arecaceae / Q000737:chemistry*; D002853:Chromatography, Liquid; D009754:Nuts / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry; D044945:Proanthocyanidins / Q000032:analysis* / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
D010936:Plant Extracts; D044945:Proanthocyanidins
Medemia argun nut; electrospray ionization; liquid chromatography; mass spectrometry; proanthocyanidins