18-6 |
Chemistry and analysis of flavonoids |
J. D. WIGHTMAN, Artemis International, Inc., 9318 Airport Dr., Fort Wayne, IN 46809 Phytonutrients are certain organic components of plants, which are thought to promote human health. Flavonoids fall under this broad description and are almost ubiquitous in the plant kingdom. They contribute significantly to the color, taste and flavor of many plants and foods. Flavonoids can impart a wide variety of colors from deep red to yellow to virtually no color at all. They are often associated with bitter and astringent flavor characteristics, but some can impart a sweet note. Different flavonoids are believed to possess anti-inflammatory, antibacterial, antiviral, antiallergenic, antithrombotic, anticarcinogenic, estrogenic, and antioxidant properties. The chemistry of flavonoids is complex and at first glance can be overwhelming. In plants, flavonoids can occur with or without sugar moieties attached. An overview of the chemistry of the various classifications of plant flavonoids will be given in this presentation as well as examples for each: including flavanols, flavonols, flavanones and isoflavanones. Identification and quantification of different flavonoids can vary greatly from thin-layer chromatography to spectrophotometry to mass spectroscopy. Various methods also exist to measure the antioxidant capacity of flavonoids in vitro. In this presentation the various methods of identification and quantification including spectrophotometric and HPLC will be described for different flavonoid compounds.
Session 18, Chemistry and analysis of phytochemicals or plant bioactive materials
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