Nuclear magnetic resonance anthocyanins

Many techniques for the analysis of anthocyanins have been used for almost a century and are still of importance, along with considerable advances in technologies such as mass spectroscopy (MS) and nuclear magnetic resonance (NMR). This section summarizes the analytical procedures for quantitative and qualitative analyses of anthocyanins, including classical and modem techniques. 

Many methods are currently available for the qualitative analysis of anthocyanins including hydrolysis procedures," evaluation of spectral characteristics, mass spectroscopy (MS), " nuclear magnetic resonance (NMR), and Fourier transform infrared (FTIR) spectroscopy. - Frequently a multi-step procedure will be used for... 

Gakh, E.G., Dougall, D.K., and Baker, D.C., Proton nuclear magnetic resonance studies of monoacylated anthocyanins from the wild carrot part 1. Inter- and intramolecular interactions in solution, Phytochem. Anal., 9, 28, 1998. 

Giusti, M.M., Ghanadan, H., and Wrolstad, R.E., Elucidation of the structure and conformation of red radish Raphanus sativus) anthocyanins using one- and two-dimensional nuclear magnetic resonance techniques, J. Agric. Food Chem., 46, 4858, 1998. 

Nerdal, W. and Andersen, 0.M., Intermolecular aromatic acid association of an anthocyanin (petanin) evidenced by two-dimensional nuclear Overhauser enhancement nuclear magnetic resonance experiments and distance geometry calculations, Phytochem. Anal, 3, 182, 1992. 

Andersen, 0.M., Opheim, S., Aksnes, D.W., and Frpystein, N.A. 1991b. Structure of petanin, an acylated anthocyanin isolated from Solanum tuberosum, using homo- and hetero-nuclear two-dimensional nuclear magnetic resonance techniques. Phytochem. Anal. 2 230-236. 

Kosir IJ, Lapornik B, Andrensek S, Wondra AG, Vrhovsek U and Kidric J, Identification of anthocyanins in wines by liquid chromatography, liquid chromatography-mass spectrometry and nuclear magnetic resonance. Anal Chim Acta 513 277-282 (2004). 

Nuclear magnetic resonance (NMR) spectroscopy is an invaluable instrumental technique for the structural determination of all flavonoids including 3-deoxy-anthocyanins. As well as providing information on the chemical environment of each proton or carbon nucleus in the molecule, the technique can be employed to determine linkages among nearby nuclei, often enabling a complete structure to be assembled. The reader is referred to Refs. 44 and 45 for details of the principles of NMR and general interpretation of NMR spectra. 

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