Spirit drinks: a source of dietary polyphenols Mrvčić, Jasna; Posavec, Sanja; Kazazić, Snježana ...
Croatian journal of food science and technology,
03/2013, Letnik:
4, Številka:
2
Paper
Odprti dostop
There is a long tradition in the production of spirit drinks and using them in the human diet, especially in the Southeast European and Mediterranean regions. The objective of this study was to ...evaluate whether and which spirits can serve, and to what extent, as a source of biologically active compounds in the human diet. Polyphenolic compounds are biologically active compounds of fruits, vegetables and derived beverages, which have been implicated in their antioxidant activity. Therefore, the total polyphenol content (TPC) and antioxidative properties of 46 spirit drinks and liqueurs produced in Croatia were examined. The total polyphenol content and antioxidant activity were estimated using spectrophotometric methods (Folin-Ciocalteu, DPPH and FRAP), while certain phenols were detected by the HPLC. It was established that spirit drinks aged in wooden casks, such as wine or plum brandy, contain polyphenols ranging from 40-90 mg GAE/L (gallic acid equivalents), whereas walnut or sour cherry liquors contain much more polyphenols ranging from 680-3360 mg GAE/L. The antioxidant activity of analyzed spirit drinks was in correlation with TPC. Walnut and sour cherry liqueur samples had very high antioxidant activity, within the range of those obtained with 1.26 mM Trolox-DPPH assay and 9.5 mM Trolox-FRAP assay.
The gas-phase reaction products of Cr^sup +^, Fe^sup +^ and Ni^sup +^ ions produced by laser desorption ionization (LDI) of a stainless steel sample with iodine molecules in a Fourier transform ion ...cyclotron resonance mass spectrometer (FT ICR MS) uncover differences in the behavior of individual metal ions in the ligation process as well as in the reactions with ubiquitous water: Fe^sup +^ being prone to ligation of two (but also to hydrolysis and disappearance), Ni^sup +^ to ligation of three and Cr^sup +^ preferring to ligate four iodine atoms. The surplus energy of metal ions produced in the excited states enables them to dissociate I^sub 2^ and exchange charge with the I^sub 2^ molecules and I atoms forming I^sub 2^^sup +^ and I^sub 3^^sup +^ ions. PUBLICATION ABSTRACT
Ligacija U+ fenantrenom u FT ICR spektrometru masa uspoređuje se s ranijim rezultatima na U+ s pirenom i fenantridinom. Svi istraženi procesi su u kompeticiji s oksidacijom U+ tragovima vode i kisika ...u instrumentu. Usporedba pokazuje da oksidacija preferira dehidrogenirane produkte ligacije.
Istraživana je ligacija različitih metalnih monokationa M+ s pirenom u plinskoj fazi. M+ (M = Al, K, V, Cr, Fe, Co, Ni, Cu, Nb, Mo, Ru, Ag, Sn, Ta, W, Re, Pt, Au, Hg, Pb, Bi and U) nastaju ...pojedinačnim udarima lasera na metalne mete unutar spektrometra masa uz Fourierovu transformaciju (FTMS) u kojem je već prisutan piren u plinskoj fazi. Do ligacije dolazi konsekutivnim adicijama uz ili bez gubitka dijela (obično H2) liganda. Ukoliko je energija ionizacije metala veća od energije ionizacije pirena dolazi do izmjene naboja. Također se opažaju reakcije dimerizacije, oksidacije s preostalim kisikom i protoniranje s prisutnom vodom u instrumentu. Napredovanje reakcija je praćeno snimanjem svih iona uz različita vremena zadržavanja u spektrometru nakon (i) udara lasera; (ii) dodatnoga izbacivanja trenutno stvorenih produkata s elektronički pobu|enim M+.
The proton affinities (PA's) of nitric oxide (NO), nitrogen dioxide (NO2), nitric acid (HNO3) as well as those of the cis- and trans-hydrogenhyponitrite (HONNO) and cis- and trans-dioxodinitrate ...(ONNO–) radicals were calculated by semi-empirical quantum mechanical calculations (standard Gaussian-2 procedure). The PA calculated values of NO (518.8 kJ mol–1), NO2 (580.5 kJ mol–1) and HNO3 (746.0 kJ mol–1) agree with the experimental values. The PA values for the NO3, ONNO– and HONNO radicals were calculated and adjusted to 580, 1330 and 770 kJ mol–1, respectively.
Investigation of simple ligation reactions of metal M+ ions with pyrene (Py) within the ICR FT mass spectrometer indicates relatively fast consecutive formation of MPy+ and MPy2+ ions, and if Ei(M+) ...> Ei(Py) accompanied also by formation of Py+ due to charge exchange. The much slower reaction and equilibrium Py+ + Py ⇌ Py2+, for which the thermodynamic parameters are known, makes it possible to determine the concentration of Py during the ligation reactions and to calculate the second order rate constants from the set of pseudo first order constants obtained by iterative nonlinear least square fitting of experimental »snapshot« mass spectral data with the proposed kinetic scheme.
The proton affinity (PA) of peroxynitrite (ONOO-) and peroxynitrous acid (ONOOH) are calculated to be 1440.5 kJ mol-1 and 749.8 kJ mol-1, respectively. Comparison with results for the nitrous, nitric ...and peroxynitric acid and their anions supports these estimates.
Hybrid density-functional calculations were carried out to corroborate the identity of phenoxyl radicals observed by EPR spectroscopy after oxidation of selected mono- and polyphenols with ...horseradish peroxidase/hydrogen peroxide or after alkaline autoxidation. Whereas quantitative correlations of experimental and theoretical coupling constants were less satisfactory, we could confirm formation of a bi-radical after initial oxidation of 2,4,6-trimethylphenol, the mesomeric structures of gallate ester aroxyl radicals and identify the radical site of a model gallotannin, hamamelitannin.
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