Determination of Flavonoids in Fruit Juice

This application note describes the use of HPLC-UV to identify flavonoids in a citrus juice sample. Separations were performed utilizing XBridge Shield RP₁₈ and XBridge C₈ columns.

Flavonoids, a group of related polyphenols derived from flavone, are widely distributed in the plant kingdom. There are more than 4000 naturally occurring flavonoids that have been identified and characterized. Among these, citrus fruit derived flavonoids and their metabolites have been shown to have significant biological activities such as anti-carcinogenic effects, anti inflammatory properties and inhibitory activities against histamine release. Figure 1 highlights a number of flavonoids and their identified properties.

This report will describe the use of HPLC-UV to identify flavonoids in a citrus juice sample. Separations were performed utilizing XBridge Shield RP₁₈ and XBridge C₈ columns.

Figure 2 illustrates the reversed-phase HPLC chromatograms of flavonoids utilizing both the XBridge Shield RP₁₈ and XBridge C₈.

Currently there is much biomedical interest in flavonoids because of their apparent health benefits. In this study HPLC analysis was utilized to identify flavonoids in grapefruit juice. This accurate identification is a critical first step towards preparative-isolation of these compounds for further analysis.

Acknowledgement

Chromatograms courtesy of Dr. John Manthey, USDA, Agricultural Research Service.