Flavonoids identification

Just as with anthocyanin analysis, the advent of HPLC/mass spectrometer coupling made it possible to avoid acid hydrolysis for flavonoid identification. Maata... 

Markham, K.R., Techniques of Flavonoid Identification, Academic Press, London, 1982. 

Before a species is analyzed with respect to its flavonoid content, knowledge about earlier reports on the chemistry and flavonoid distribution within the genus and related species may be of value. The most exhaustive source for such information is Chemical Abstracts, and excellent reviews on structures and distribution of flavanoids have been compiled regularly.Several reviews have recently addressed the general field of flavonoid analysis.Among the earlier reviews in the field, we will particularly recommend consulting Techniques of Flavonoid Identification by Markham and Plant Phenolics by Harborne. References to review articles on specific spectroscopic techniques applied on flavonoids will be cited under the various spectroscopic methods covered in this chapter. Spectroscopic information of importance is also presented in several other chapters in this book. 

Flavonoid identification methods were those of Mabry et al. 

Day AJ, Mellon F, Barron D, Sarrazin G, Morgan MRA, Williamson G. 2001. Human metabolism of dietary flavonoids identification of plasma metabolites of quercetin. Free Radic Res 35 941-952. 

Flavonols and flavones are present in many food products and medicinal plants and show relevant antioxidant activity in vitro. In this chapter, classical analytical methods sueh as thin layer ehromatography and two-dimensional paper chromatography together with modem methodologies such as HPLC-MS-MS are reported. Preparative ehromatography methods are also reviewed as well as spectroseopie methods used for flavonoid characterization and identification, including UV spectrophotometry and MS spectrometry. Chemical and enzymatic methods used in flavonoid identification are also reviewed. 

K.R. Markham,"Techniques of Flavonoid Identification", Academic Press, New York, 1982. 

Markham K R 1982 Techniques of flavonoid identification. Academic Press New York... 

The most common method for flavonoids identification and quantification is UV-visible (UV-Vis) detection. Havonoids have two characteristic absorption bands in the UV-Vis region. Band I (arising mainly from the B- and C-rings of the flavan nucleus) and Band II (from flie A-ring), with absorption maxima in the 300-550 and 240-285 nm range, respectively. Figure 3.3 shows UV-Vis spectra representative... 

Day, A.J., Mellon, R, Barron, D. etal. (2001) Human metaboHsm of dietary flavonoids identification of plasma metaboUtes of quercetin. Free Radic. Res., 35, 941-952. 

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