ABSTRACT
The interest in chlorogenic acids (CGAs) and other hydroxycinnamates has expanded rapidly in the past 5-10 years. Numerous epidemiological studies have frequently linked the consumption of a diet rich in CGAs with numerous bene‚cial health effects (Czok, 1977; Tavani and Vecchia, 2000; Dorea and Da
21.1 Introduction ................................................................................................................................. 461 21.2 Classes of Compounds ................................................................................................................ 462 21.3 Chlorogenic Acids: De‚nition, History, and Dietary Burden .................................................... 462 21.4 Chlorogenic Acids: The Isomer Problem ................................................................................... 465 21.5 Chlorogenic Acids: Food Processing and Metabolism ............................................................... 465 21.6 Characterization of Chlorogenic Acids by UV-Vis Spectroscopy ............................................. 466 21.7 Quanti‚cation of Chlorogenic Acids by UV-Vis Spectroscopy ................................................ 468 21.8 General Comments on Liquid Chromatography of Chlorogenic Acids ..................................... 470 21.9 Characterization of Chlorogenic Acids by NMR Spectroscopy ................................................ 470 21.10 Limitations of NMR Spectroscopic Analysis ..............................................................................471 21.11 Characterization of Chlorogenic Acids by IR Spectroscopy .......................................................476 21.12 Molecular Modeling and Spectra Prediction .............................................................................. 477 21.13 Quantum Mechanical Calculations ............................................................................................ 477 21.14 Calculation of NMR Chemical Shifts of Caffeoylquinic Acids ..................................................478 21.15 Mass Spectrometry and Chlorogenic Acids Identi‚cation ..........................................................478 21.16 Work Flow for Chlorogenic Acid Pro‚ling, Identi‚cation, and Structure
Elucidation by LC-Tandem MS .................................................................................................. 479 21.17 LC-MS and LC-MSn Identi‚cation of Chlorogenic Acids in Food Materials ........................... 482
21.17.1 Green Coffee Beans ...................................................................................................... 482 21.17.2 Roasted Coffee .............................................................................................................. 490 21.17.3 Maté Leaves ...................................................................................................................491 21.17.4 Other Food Materials .................................................................................................... 493
21.18 Miscellaneous Characterization Techniques for Chlorogenic Acids ......................................... 496 21.19 General Comments on Other Hydroxycinnamic Acid Derivatives ............................................ 497 21.20 Pharmacokinetic Studies of Chlorogenic Acids and Metabolites .............................................. 500
21.20.1 Crozier Study ................................................................................................................ 503 21.20.2 Farah’s Studies .............................................................................................................. 503 21.20.3 Critical Comparison and Discussion ............................................................................ 504
Acknowledgments .................................................................................................................................. 506 References .............................................................................................................................................. 506
Costa, 2005; Hamer et al., 2006; Higdon and Frei 2006; van Dam, 2008; Crozier et al., 2009; Risken et al., 2009). Further interest in this ubiquitous class of compounds is due to their interesting sensory and organoleptic properties (Frank et al., 2007).
