Flavonoids are polyphenolic compounds produced by plants that are thought to provide health benefits when consumed as part of a diet rich in fruits and vegetables, such as citrus, spinach, blackberries, kiwi, garlic, broccoli, and carrot. It is believed that the flavonoids found in foods may protect the human body against heart disease, and cancer. Over 4,000 flavonoids have been identified, each with a unique chemical combination of shape, polarity, and molecular weight. The chemical structure of a flavonoid influences its ability to scavenge free radicals. Previous studies have shown that polyphenolic compounds produced in sagebrush exhibit antioxidant activity. My project was to identify the types of flavonoid found in different sagebrush species by comparing their properties with those of known standards. Reverse phase High Performance Liquid Chromatography(RP-HPLC) was used to separate polyphenol standards and those extracted from sagebrush based on their hydrophobicity. Flavonoids were compared using their retention time over a C18 RP- HPLC elution. A flavonoid standard library was constructed to compare with sagebrush derived flavonoids. Each flavonoid standard only showed one peak on the HPLC elution profile with a specific retention which was compared with the peaks exhibited by sagebrush polyphenols. Twelve flavonoid standards were characterized showing 12 distinctive peaks with their respective retention times.

Using a Standards Library to Identify Flavonoid Compounds in Sagebrush Extracts