Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) as a new valuable technique has been used for qualitative screening of anthocyanins in wine and grape samples from Vranec and Merlot variety. For that purpose, different MALDI matrices have been tested, such as α-cyano-4-hydroxycinnamic acid, sinapic acid, 2,5-dihydroxybenzoic acid (2,5-DHB), and C70 fullerene. It was observed that 2,5-DHB was superior with respect to all the matrices used in the study. Furthermore, fullerene was, for the first time, tested and used as a possible matrix for MALDI-TOF-MS identification of anthocyanins in wine and grape samples. The results obtained showed identification of aglycone forms of anthocyanins only, since the higher laser energy applied for ionization of the fullerene molecules led to great deal of fragmentation of the sugar moiety from glucosides, acetylglucoside, and p-coumaroylglucoside groups from the corresponding anthocyanin molecules. Additionally, liquid chromatography/electrospray ionization mass spectrometry has also been applied for anthocyanin characterization.
Anthocyanins 2,5-DHB CHCA SA Fullerene MALDI-TOF-MS LC-MS Wine Grape
The authors acknowledge the CEEPUS Program realized through the CEEPUS network (CIIHU-0010-01-0607—Teaching and learning bioanalysis) for the given opportunity and financial support for performing the MALDI-TOF-MS analyses at Department of Biochemistry and Medical Chemistry, Faculty of Medicine, at the University of Pécs, Hungary. The work was also supported by the grants GVOP-3.2.1-0168, GVOP-3.2.1-0179, RET 008/2005, OTKA 46476, OTKA-NKTH NI-68863, and DDEK Nonprofit Kft.